On my very rasonably spec'd laptop it often takes 20 seconds for the snipping tool selection to pop up. Video recording is very nice though, definitely my favorite feature.
New Notepad had a broken typematic that took them 2 years to fix, but they added Copilot at the same patch. Resizing its window still rapidly still flickers and can max the CPU.
If you're using labels in the taskbar the buttons aren't fixed width, they resize to fit the window title - except that until recently they didnt, so if you cd from C:\ to a longer path you got the label "C...". That one is fixed, but not the one where I switch desktops with Ctrl+Alt+arrows and the entries have no icons.
If you have a folder with lots of audio files, sometimes explorer.exe will hang for 30 seconds while it dutifully extracts artist metadata (no way to disable). Possibly an old issue, but I've never hit it before.
Search is even worse than before, I have "alacrity.exe" both in PATH and as a shortcut on desktop, but when I type "alacr" I get a web suggestion until I fully type it out. "Visual..." toggles between VSCode and fat visual studio on every keypress.
I can't express my opinion on the Task Manager changes without using language inapropriate for this forum.
Those are my issues off the top of my head, if I record every single broken thing I see for a week this list would be way longer.
That's just the stuff that doesn't work, there's a similarly long list of things that work but are evil.