Yes sir, absolutely, the earliest Thirumal poem extant is Paripadal of Sanga kalam. Thirumal is certainly a Tamil god, along with Murugan.
Later, in Silappathikaram Ilango describes a scene in a cowherd village outside Madurai where Kannaki was awaiting Kovalan who had gone into the city for raising money by selling her Silambu. Kannaki was downcast after seeing bad omens. To cheer her up the women of the village gather around to sing and dance the praise of Thirumal. The words of this song was popularized by M.S. -- vadavaraiyai maththaakki. It is a wonder that a Jain could come up with such grand and beautiful verse in praise of a god he himself did not believe in!
Even the earliest of Azhvars sing the praise of many Vishnu temples. Thirumangai Azhvar, one of the later Azhvars and by some accounts the last one, starts out from Badri and Saligramam of Nepal and sings of various temples all the way down to Pandiyan country. Nammazhvar also sings of Perumal temples all over, including ones along Kerala from TVM up to Thiruvalla and beyond. From this we can safely conclude Thirumal worship was quite widespread in Tamil country by the time of the Azhvars.
We also find in Azhvar pasurams a few concepts that may not have been there during the time of Paripadal, (i) Thirumal is praised as a Vedic god, (ii) seeing Sriman Narayana as the supreme Iswara/Para-brahman lording over all other gods, and (iii) exclusive worship of Thirumal.
Then came the early SV acharyas starting with Sriman Nathamuni and reaching intellectual zenith during Ramanuja who wrote Sri Bhashyam and forever made SV into a Brahmnical religion. However, I believe Ramanuja himself was not a confirmed casteist, his use of Gauthama and Manu DS in his Sri Bhashyam not withstanding. He is supposed to have pressed lot of NBs into different SV service and promoted temple entry for untouchables three days a year in Melkottai. But, he did not, or probably could not, go far enough. Even the few small things he did he was constantly questioned.
During Ramanuja's time there must have been an influx of Vadamas joining the ranks of SVs. In due course of time they imposed all the Varna rules that were sort of loosened by Ramanuja a little bit. They also wrote elaborate commentaries of Azhvar pasurams arguing they were consistent with Dharmashasthra rules.
They wrote (or rewrote) Azhvar stories to show they themselves did not transgress any of the oppressive varna rules and argued the Azhvars had great respect for them. One story they love to tell is of Thirumazhisai Azhvar. On his travels one day he came towards a Brahmana goshti chanting Vedas. These Brahmanas, seeing this "shudra" approaching stopped the chanting. Later, for reasons I won't go into here, they wanted to resume their chanting in the presence of the "shudra" Azhvar himself, but had forgotten where they stopped. Then, the Azhvar took a grain of paddy and split it to remind them of where they need to resume. The upshot being, Azhvar knew the Vedas better than anyone else, but still would not utter even one word of it to remind these Brahamanas because of respect for DS rules.
Thus came to a sorry end any hope of continuing the reforms Ramanuja started. The SV Brahmins managed to make everyone believe Azhvar's world-view was nothing different from their own varna-based word view. This is the reason we see objections from Raju. For him and others who share his view, those Acharyas knew what the Azhvars true intents were -- திருவுள்ளம் -- anything contrary is twisting and misinterpreting.
For example, Azhvar only says தொழுமின், கொடுமின் கொள்மின், which can be interpreted expansively or narrowly. These acharyas chose to be narrow and restrict it to simply falling at their feet, exchanging vidya, and accepting Sri Pada Theertam. In their interpretation these words did not mean exchanging girls in marriage. Later, this got further narrowed to just anjali (not falling at the feet), ordinary vidya exchange and not take NB as acharya. Today, often it is not even this and may very well include open derision like, "போ போ பின்னாடி போய் நில்லுங்கோ".
All reforms were put back in the bottle and thrown away by the time of Swami Sri Desikan, about 750 years ago. He is the one who wrote NB devotee is like a temple cow, however great he may be, he is still a cow only. We may respect that cow for being a temple cow, but can't fall at his feet or take him to be an acharya.
Thus, the SVs do not see any disharmony between the Azhvars' view and those of the post-Ramanuja seers. Only those of us who twist and misinterpret see such disharmony
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Cheers!
p.s. SV = Sri Vaishnavam, a particular form of Vaishnavam practiced in South India, one in which Lord Narayana and his consort Mahalakshmi are considered inseparable two in one deity, divya dampathi, who grant moksham.
