I think your post, while meaning well is also disingenuous. This is cause of how much you seem to know about what you are saying and then the somewhat strange conclusion you arrived at.
Two things, first. No developer "gimps" a game for parity. Its kinda impossible to do when you think about it. Cause to accomplish it would mean that you would have to put in extra work to make the game run worse. This misconception is based off gullible people either believing what they see of games either in bullshots or extremely early in development footage or footage running off industrial grade hardware.
Secondly, this isn't all some sort of conspiracy. Its really straight forward. When a developer sets out to make a game, they always have a target in their head (this part you touched on and i agree with). If a deveoper is making a multiplatform game, then what they would do is simply try and optimize the game for weakest hardware. Simply cause if they get it running on the weakest hardware then everything else can run it.
What consoles represent to PCs is the minimum best standard, cause as console hardware become more similar to PCs, developers can just focus on the console knowing that PCs would be able to run them just fine. But no one sets out to gimp a game in the name of parity.







