If you don't personally like TES lore that's fine, I mean I don't get how someone can think Morrowind is anything other than a tour de force of worldbuilding that's rarely been matched in any media, nevermind videogames, but that's your business.

But you really are fundamentally failing to understand how it is constructed, how the community functions, and how something becomes 'TES lore'. Pike's already tried to explain and I'm not sure if it's something you're failing to grasp or that she's getting wrong that I can't see but I'll give it a try as well.

TES lore is fundamentally written by the developers. People like Michael Kirkbride sit down and come up with ideas and write plots, quests, in-game books, and so on. Some of this is very obvious stuff, such as when you ask someone "What is Red Mountain?" and some of it is exceedingly subtle, such as the way different Ashlander tribes have different styles of clothing based on where they live and the resources (leathers, chitin, plants, etc.) which they have easy access to. There is an absolutely tremendous, astonishing amount of lore in the TES games but one of the fundamental points is that a lot (almost all, in fact) of it is neither concrete nor perfectly relayed. For example, in Morrowind again, you never find out what exactly happened during the Battle of Red Mountain; Why did the Dwemer disappear? Was Dagoth Ur doing his job and struck down by a traitorous superior, or did he covet tremendous power and refuse to turn over the instruments he was charged with protecting? So on and so forth, about a great many issues and events.

This is fundamentally good storytelling in principle, because presenting conflicting and unclear accounts helps to establish and embellish differing motivations and does so in a way that is much better than simply spelling out everyone's ideas and telling the 'reader' what really happened. It's something that's dreadfully lacking in most games because motivations are given in a very clearcut fashion and you know for yourself whether something is accurate or not with certitude.

But what has happened with TES, and Morrowind especially, is that this huge body of lore has been engaged with by people who enjoy it and get into it. If you don't, that's fine, but that's not the point - the point is that there is a huge collaborative effort to understand and discuss this lore. And, yes, if someone comes up with a particularly interesting interpretation or novel idea that might become accepted by the TES Lore Commmunity as 'canon'. That does not mean it is going to be the main plot of the next game, or included in any way in the next game. What it does mean is that it is a coherent addition which augments the setting or which provides a new twist on something and one which the community as a whole - often with some dev input, often without - has decided fits the setting and thus can be considered a part of the overall mythos.

I'm not entirely sure to what extent this can be understood without being involved in the community personally because it's a complex community effort and whilst I don't want to seem elitist or to be snubbing anyone, an 'outsider' (for want of a better term) probably won't grasp it all. But, again, at the base of it you quite simply wouldn't have a still active, busy fandom coming up with new ideas, new fanart, new points and interpretations, if the lore in the thing that sparked it wasn't immense.