I've written about my experience with macOS Catalina on an earlier thread:
https://news.ycombinator.com/item?id=23273467Since then there have been new developments:
Had a meeting yesterday, 5 minutes before the scheduled time (which is normally plenty of time when your tools work as expected) I start up Zoom and create the meeting. Guess what? The thing now just freezes completely and it's not just Zoom, the system UI (dock, menu bar, etc) becomes sluggish. This used to work fine before upgrading to Catalina. Force-quitting Zoom fixed it, so I'm assuming something Zoom is doing (that used to work fine) is enough to completely freeze the system UI.
Eventually gave up on Zoom and used FaceTime. In the middle of the call the UI froze for ~10 seconds - no video, no mouse, but audio was still working. I assumed it would crash but thankfully it recovered.
Finally after the call I left the machine unattended for a minute and when I got back it was on the full disk encryption password screen so it had rebooted. Turns out it crashed because WindowServer stopped responding. I heard about those issues but always though it's related to the newer models with discrete GPUs and I didn't have to worry about it with my low-end Macbook with Intel graphics. I guess I was wrong.
Mail is still playing the new mail sound randomly when archiving/moving read messages, and I ended up disabling the sound completely. I didn't know it was possible to screw up something so simple.
I am now thinking of downgrading and using Catalina (for Xcode) on a separate machine. I am not sure what to do when it goes out of support though, seems like nowadays every OS became equally shit.