I am aware of the very strange position that Augustine has in the east as both being a Saint and author of multiple heretical texts.
The East doesn't consider him the author of heretical texts, canonically.
On the other hand, he does offer good evidence that universal salvation was either the majority view of the Western Church in his time or at the very least had a large presence.
That's an equivocation. Either it was the majority position or it wasn't, and even if it had a "large presence"-- whatever that means-- that doesn't vindicate the position within the confines of Christian doctrine as informed by Scripture and the historical tradition in which it was formed and inhabits. I'd be inclined to say that "large presence" means "warranted being addressed by a council", but councils back then were convened conservatively to dogmatize on
really controversial issues (e.g. Arianism). If it took the Fifth Ecumenical Council for it to be addressed, as an item within a collection of beliefs (Origenism), which was addressed beside another particular belief (Nestorianism),
and you didn't see break aways after the dogmatizations like you saw from particularly the Fourth Ecumenical Council, that all strongly implies the condemnation of universalism by council wasn't controversial, and thus wasn't an important doctrine.
But it
would be an important doctrine, because it describes a particular eschatology.
That, by itself, suggests that there was no strong contingent within the presbytery that taught universal salvation.
Universal salvation wasn't not initially declared heretical by the eastern church but the Emperor Justinian.
You misunderstand the point of dogma if you're saying this. You likely mean to suggest that he strongarmed the Church into condemning the doctrine of universal salvation, except that you've repeatedly had clerics and the like go as far as resisting the empire (e.g. Athanasius, Maximus) for the sake of orthodox doctrine (or at least, what they consider such)-- if there was a strong contingent that believed in universal salvation, there would have been struggle about this specific matter.
Secondly, and most importantly, I reiterate what I said before: dogma, historically, and particularly in an
ecumenical council, was only declared under what were recognized as extreme circumstances. The Trinity was declared dogma in the First and Second Ecumenical Councils, for example, because of the great disturbance that Arianism (and its lookalikes) had been causing within the Church (and as far as the emperor was concerned, the empire). If it wasn't a controversy that was seen as demanding a council (of any kind), they didn't convene a council.
That doesn't mean that something wasn't doctrine before its dogmatization, or that it wasn't understood as orthodox doctrine. Dogmatization is meant to enshrine orthodox doctrine when said doctrine is vigorously opposed, to the detriment to the unified pedagogical and liturgical capacities of the Church. If universal salvation wasn't addressed until the Fifth Ecumenical Council, while that could mean that it was accepted before it wasn't (such is a rather cynical viewpoint), it more than likely means that
until then, the Church ecumenical didn't see it as an impediment to its functions
because it wasn't actually popular enough to warrant more than stern warnings and excommunications.
If the doctrine of universal salvation was condemned as part of Origenism, that doesn't mean that it wasn't condemned particularly. They didn't say "we condemn Origenism", they said "we condemn such and such teachings of Origen". Origen
was a Christian (however "mad scientist" he was with his doctrines), and some of his teachings were referred to in the development of the doctrine of the Trinity.
...but we're talking about the
second Origenist crisis.
Religious authorities will always leverage the threat of divine punishment to coerce secular authority.
Weren't you suggesting that
Justinian, somehow, declared the doctrines heretical?
I would however contend that you're simplifying the Orthodox Church's view of salvation.
I mentioned "the Eastern Churches", which would include the (Eastern) Orthodox Church, the (Oriental) Orthodox Church, and the Assyrian Church of the East.
All of them believe in eternal damnation. Stating this isn't an oversimplification of doctrine-- that's a statement about a segment of a particular doctrine they all have. I could mention that the Eastern Orthodox largely believe that "heaven" and "hell" are particular experiences of God's presence by the soul (as all souls return to God), and that the soul opposed to God "experiences hell", but outside of that, souls ultimately tended towards God experience different levels of Purgatory-
ish purification as part of their continued theosis, including maybe none at all.
But that's not relevant to this discussion. "Denominations" aren't relevant, because we weren't speaking of denominations.
Religious people won't like this but there is a reason Atheism tends to correspond with a higher level of education; Atheists may not be innately smarter or have higher IQ's but they do tend to be more rational and that is a skill that can be learned by most, but not all people.
You're asserting that higher levels of education is
synonymous with greater rationality? Let's forget that institutions of learning were initially religious, and for the longest time, the only way you were going to be strongly literate (if at all) outside of being of higher class was to become a priest or monk--
have you been to universities?