What does Sri Ramanuja mean by saying "Pasupati-Mata' is 'Anadaraniya'?
Because according to the Brahma Sutras, the Shaiva Agamas contain some teachings that are in conflict with the Vedas.
From the "Pasupati Adhikarana" of the Brahma Sutras:
(The system) of the Lord [Pati] (must be disregarded), on account of inappropriateness.
And on account of the impossibility of rulership.
If you say, as in the case of the organs; we deny this, on account of enjoyment and so on.
Finiteness or absence of omniscience.
And part of Ramanujacharya's commentary for sutra 36:
The Sûtras now declare that, for the same reasons, the doctrine of Pasupati also has to be disregarded. The adherents of this view belong to four different classes--Kâpâlas, Kâlâmukhas, Pâsupatas, and Saivas. All of them hold fanciful theories of Reality which are in conflict with the Veda, and invent various means for attaining happiness in this life and the next. They maintain the general material cause and the operative cause to be distinct, and the latter cause to be constituted by Pasupati. They further hold the wearing of the six so-called 'mudrâ' badges and the like to be means to accomplish the highest end of man.
This is the main reason why many Shaiva sects reject the Brahma Sutras and the Vedanta school.
However, Ramanujacharya says the Brahma Sutras support the Pancharatra Agamas:
That this worship of that which is of a fourfold nature means worship of the highest Brahman, called Vâsudeva, is declared in the Sâtvata-samhitâ
...
That the Bhâgavata doctrine is meant to facilitate the understanding of the sense of the Veda which by itself is difficult of comprehension, is declared in the Paramasamhita