If removing "features" improves performance, one has to wonder how much overhead those features have.

If I remove the UI/window manager from Linux and run software from the command line, I don't see a massive performance boost. That's not to say I would run a server with the UI, but it's not like I'm seeing a 100% improvement or anything. Thus, there must be some difference between the acceptable overhead of Linux vs. Windows.

It just makes me think that Windows continues to add features as long as that n+1 feature doesn't slow down the PC, and thus doesn't stop until the PC is slowed down. Thus, every Windows OS will have a maximal amount of overhead.