The talos mistake seems like an utterly biased and unreliable source... a tool used by bethesda to show you that in-game books cannot be always be trusted... dammit they were preparing for this "retconn" for a while!
Again, Talos Mistake is what? A literary tool, shown by Bethesda. It gives you a clear view of what the Aldmeri Dominion believes, with every second Nord on the street disagreeing (and I believe a book from Skyrim may call Talos Mistake total BS, a book written by a Nord, I forget). The author specifically mentions they're from the Aldmeri Dominion. THIS is perfectly ok. I am not complaining that Talos Mistake isn't treated as 100% truth because Skyrim makes it clear it's an OPINION by providing counter-arguments to it.
Which again, is exactly my point: the books we find in games are tools of literature that we're supposed to use to better understand the TES universe.
That Immortal Blood had no book that opposed it's views? Sends the message it should be taken seriously.
That the Volkihar are now going in a completely different direction than what we previously heard? Obvious retcon.
Stop trying to justify a retcon and admit it's a retcon. That's exactly my complaint.
I, personally, am not fond of being told "Redguard hate magic!" and then next game lolwtfbbq they luvs dem sum magic.
I, personally, am not fond of being told "werebears are a real problem in Skyrim" and then come Skyrim I'm standing with M'aiq going "werebears? Where?"
I, personally, am not fond of being told the Volkihar are unique because of this and that, then come Skyrim they're half Cyrodiil strain, half Underworld movie.
I, personally, am not fond of being told about Shadowscales as if they were an important part of Argonian culture, then come next game they say "everything we taught you last game? Yeah forget it lolololollolol."
It's bad writing, simple as that. I have zero problem with TES wanting some sources to be unreliable sources in game, but that needs to be made clear. Do I complain about Morrowind, which was full of contradictions? No, because it was clear those contradictions were intentional and those sources were not meant to be reliable. Skyrim? No, these are retcons. Learn 2 write, Bethesda. You used to be able to...