Windows 7 UI was a bit too flashy and employed looks over readability and Windows 98 was too old fashioned and also suffered from a lack of contrast with all the grey.
https://git.sr.ht/~q3cpma/website/tree/master/item/src/resou...
https://world-playground-deceit.net/
These make me want to go all the way.
I don't want to discard whatever innovation has been done, but man I find myself being nostalgic of old UI quite often.
As with a lot of things in ux accessibility research, these results were never replicated but the idea was seared into all our brains permanently. We know from research on fonts that ultimately, the most accessible font is the one the user is most used to. Sans vs. Serif vs. etc all don't seem to make a consistent difference across demographics. I suspect line spacing is something that's due for a relook