About this part, I'm not sure I understand.

"deMicrosoft" was, and is a thing. See "windows 7 umattended edition" or "windows 10 reclaim scripts". Same with android and custom roms.

Corporate greed bloats up perfectly fine operating systems for as long as I can remember, and de-bloating them has and is still a thing.

Stock android is not so bad (2023); android has to cater to a broader ecosystem of vendors and hardware, hence the heterogenity and the overall not streamlined experience that comes with it, that much is certainly true.