There are issues like the requirement of a microsoft account, there are issues with snapping windows and global hotkeys and every piece of software needing its own bespoke update mechanism (often interrupting you while doing things).
Theres issues with ransomware, theres deep seated issues with the default filesystem which not only has abysmal performance but also does absurd cache things making it behave extremely strangely with even minor bit flips. I have never experienced inaccessible files except on windows. The permissions system btw requires a damn PhD to understand if you have more than one user on the system.
Or the fact that errors are by default opaque and hidden, the event logger is practically useless both providing no information relevant to the issue and simultaneously far too much information so you drown in irrelevance.
As a power user, windows is about as hostile as it possibly could be.
As a normal user the experience is really unclean, the 17 pop-ups I get when installing and the forced online account are enough, but honestly the weight of the OS is so much: you literally cant even run the thing on a standard spinning drive anymore.
This is exclusively an issue with Xorg. (as the other commenter also mentioned), the Wayland OOB experience is pretty solid these days, as much hate as Wayland got these are the real problems that it was designed to solve properly.
I would love to hear other complains, 100% linux to 100% windows is quite a strong transition, definitely not one I'd be comfortable making so your situation must have been mired with issues much larger than feeble mixed DPI support; because honestly speaking Windows has significantly larger issues than that.