It really depends upon what your intentions are and how you go about doing it. Krishna says in the Gita 18.24-25 (Swami Nikhilananda translator):
To invest in bitcoins is gambling. No product is produced and you only gain money at the expense of others. They may be faceless and nameless, but it is still at others expense. Such types of 'investments' are tamasic.
The householder marries and carries on his duties as a citizen, and the duty of the other is to devote his energies wholly to religion, to preach and to worship God. I shall read to you a few passages from the Mahâ-Nirvâna-Tantra, which treats of this subject, and you will see that it is a very difficult task for a man to be a householder, and perform all his duties perfectly:
The householder should be devoted to God; the knowledge of God should be his goal of life. Yet he must work constantly, perform all his duties; he must give up the fruits of his actions to God.
It is the most difficult thing in this world to work and not care for the result, to help a man and never think that he ought to be grateful, to do some good work and at the same time never look to see whether it brings you name or fame, or nothing at all. Even the most arrant coward becomes brave when the world praises him. A fool can do heroic deeds when the approbation of society is upon him, but for a man to constantly do good without caring for the approbation of his fellow men is indeed the highest sacrifice man can perform. The great duty of the householder is to earn a living, but he must take care that he does not do it by telling lies, or by cheating, or by robbing others; and he must remember that his life is for the service of God, and the poor.
Knowing that mother and father are the visible representatives of God, the householder, always and by all means, must please them. If the mother is pleased, and the father, God is pleased with the man. That child is really a good child who never speaks harsh words to his parents.
Before parents one must not utter jokes, must not show restlessness, must not show anger or temper. Before mother or father, a child must bow down low, and stand up in their presence, and must not take a seat until they order him to sit.
If the householder has food and drink and clothes without first seeing that his mother and his father, his children, his wife, and the poor, are supplied, he is committing a sin. The mother and the father are the causes of this body; so a man must undergo a thousand troubles in order to do good to them.
Even so is his duty to his wife. No man should scold his wife, and he must always maintain her as if she were his own mother. And even when he is in the greatest difficulties and troubles, he must not show anger to his wife.
He who thinks of another woman besides his wife, if he touches her even with his mind — that man goes to dark hell.
Before women he must not talk improper language, and never brag of his powers. He must not say, “I have done this, and I have done that.”
The householder must always please his wife with money, clothes, love, faith, and words like nectar, and never do anything to disturb her. That man who has succeeded in getting the love of a chaste wife has succeeded in his religion and has all the virtues.
The following are duties towards children:
A son should be lovingly reared up to his fourth year; he should be educated till he is sixteen. When he is twenty years of age he should be employed in some work; he should then be treated affectionately by his father as his equal. Exactly in the same manner the daughter should be brought up, and should be educated with the greatest care. And when she marries, the father ought to give her jewels and wealth.
Then the duty of the man is towards his brothers and sisters, and towards the children of his brothers and sisters, if they are poor, and towards his other relatives, his friends and his servants. Then his duties are towards the people of the same village, and the poor, and any one that comes to him for help. Having sufficient means, if the householder does not take care to give to his relatives and to the poor, know him to be only a brute; he is not a human being.
Excessive attachment to food, clothes, and the tending of the body, and dressing of the hair should be avoided. The householder must be pure in heart and clean in body, always active and always ready for work.
To his enemies the householder must be a hero. Them he must resist. That is the duty of the householder. He must not sit down in a corner and weep, and talk nonsense about non-resistance. If he does not show himself a hero to his enemies he has not done his duty. And to his friends and relatives he must be as gentle as a lamb.
It is the duty of the householder not to pay reverence to the wicked; because, if he reverences the wicked people of the world, he patronizes wickedness; and it will be a great mistake if he disregards those who are worthy of respect, the good people. He must not be gushing in his friendship; he must not go out of the way making friends everywhere; he must watch the actions of the men he wants to make friends with, and their dealings with other men, reason upon them, and then make friends.
These three things he must not talk of. He must not talk in public of his own fame; he must not preach his own name or his own powers; he must not talk of his wealth, or of anything that has been told to him privately.
A man must not say he is poor, or that he is wealthy — he must not brag of his wealth. Let him keep his own counsel; this is his religious duty. This is not mere worldly wisdom; if a man does not do so, he may be held to be immoral.
The householder is the basis, the prop, of the whole society. He is the principal earner. The poor, the weak, the children and the women who do not work — all live upon the householder; so there must be certain duties that he has to perform, and these duties must make him feel strong to perform them, and not make him think that he is doing things beneath his ideal. Therefore, if he has done something weak, or has made some mistake, he must not say so in public; and if he is engaged in some enterprise and knows he is sure to fail in it, he must not speak of it. Such self-exposure is not only uncalled for, but also unnerves the man and makes him unfit for the performance of his legitimate duties in life. At the same time, he must struggle hard to acquire these things — firstly, knowledge, and secondly, wealth. It is his duty, and if he does not do his duty, he is nobody. A householder who does not struggle to get wealth is immoral. If he is lazy and content to lead an idle life, he is immoral, because upon him depend hundreds. If he gets riches, hundreds of others will be thereby supported.
If there were not in this city hundreds who had striven to become rich, and who had acquired wealth, where would all this civilization, and these alms-houses and great houses be?
Going after wealth in such a case is not bad, because that wealth is for distribution. The householder is the centre of life and society. It is a worship for him to acquire and spend wealth nobly, for the householder who struggles to become rich by good means and for good purposes is doing practically the same thing for the attainment of salvation as the anchorite does in his cell when he is praying; for in them we see only the different aspects of the same virtue of self-surrender and self-sacrifice prompted by the feeling of devotion to God and to all that is His.
He must struggle to acquire a good name by all means. He must not gamble, he must not move in the company of the wicked, he must not tell lies, and must not be the cause of trouble to others.
Often people enter into things they have not the means to accomplish, with the result that they cheat others to attain their own ends. Then there is in all things the time factor to be taken into consideration; what at one time might be a failure, would perhaps at another time be a very great success.
The householder must speak the truth, and speak gently, using words which people like, which will do good to others; nor should he talk of the business of other men.
The householder by digging tanks, by planting trees on the roadsides, by establishing rest-houses for men and animals, by making roads and building bridges, goes towards the same goal as the greatest Yogi.
This is one part of the doctrine of Karma-Yoga — activity, the duty of the householder. There is a passage later on, where it says that "if the householder dies in battle, fighting for his country or his religion, he comes to the same goal as the Yogi by meditation," showing thereby that what is duty for one is not duty for another. At the same time, it does not say that this duty is lowering and the other elevating. Each duty has its own place, and according to the circumstances in which we are placed, we must perform our duties.
The accruing of wealth by just means is encouraged by scriptures. If done correctly it is done for the betterment of society as a whole. To do it by unjust means is condemned.