I've used Windows 10 on a 4K monitor at 200% for a couple years and I didn't have any issue. macOS' scaling works best, but Windows has been HiDPI ready for a while, and only a small handful of old apps need you to enable the application-scaling option manually. Especially since Windows still runs 15 years old applications that use crappy old APIs, while macOS doesn't.
It's not fantastic by any means, but it's a disservice to call it _horrible_.