I'm gonna say something on that now, and please understand from my other posts you will know that I'm not jumping up and down claiming it's all related to the Xbox. Word post kinda makes me laugh (not in a bad way, or a mocking way)
"they would also have to assume that gamers are blithering idiots with no concept of the difference between consoles and premium graphics cards." it's not funny because you said it. It's not even funny because I think it may or may not be true. What I find funny is that a lot of people don't seem to have noticed the drop in graphics quality. There was even a huge thread on Reddit where a lot of people were saying they 'prefer the quality of the new graphics', and then it turned out the 'new graphics' were bugged and merely the low quality setting being displayed instead of ultra. Whilst I understand that subjectively some people may prefer the appearance of low quality over the appearance of ultra quality...objectively it is a bit of a "blithering idiot" statement.
This isn't really related directly to what you were actually saying. It's just that a whole segment of the community either seem to not notice or not care about the reduction in graphical quality.
It's frustrating to see people arguing over theories (crack pot or otherwise) as to why the graphics have changed. When really we should be presenting a united front to Frontier and asking for a far more detailed explanation and update on what is happening with the graphics. It's a FACT that that the graphics have changed and that in many places they now look worse. We know some of that is due to bugs - we don't know if Frontier intend for fix them. We also know that some of it is due to optimizations - we don't know if we will ever get the option for high end PC's to re-enable the higher quality versions. And finally there are a bunch of graphical changes that we have no clue what has happened with them one way or another. All we know for sure, is that in a lot of places the game no longer looks as good as it once did. We can argue over theories, and we can argue over subjective preference. But none of that changes the objective facts. (And yes, I think you are probably right - this isn't intentionally down to the Xbox, and I believe Frontier when the say that. But it's possible that some unintended changes have snuck their way into the PC build).