They "fixed" their game mode which led to alot of issues across multiple games (bad broken graphics, third party interfaces not working, the worst fps dips i've ever seen). You have to remove its files to fully be rid of Game Mode due to them removing the On/Off button. I really only had a big issue and still do with FFXIV, but they are slow to update as well so who knows (the dips are real, and they don't come with chips

). It also reset alot of power management settings, effectively eliminating some of them for some people (mine was just "hidden"), completely jacked up my sound/mic settings across most things that rely on windows to get that stuff together, among other things. That's just what I've experienced for I know it doesn't happen to everyone, I dodged every bullet in the spring creators update.... It's not gaming ending, but....it takes way longer than it should to hunt down most of these issues and fix them. Other people reported stuff with edge and windows apps but I don't use those; and graphics drivers (was already fixed by Nvidia by the time I got the update). I'd also like less spying and more control over my own windows settings but those days seem to be limited...
It's updates like these that make me appreciate how consoles just turn on and work. (for the most part but even they can have bad updates too)