I remember when macOS Big Sur came out people in the programming / comp bio world were saying to avoid installing it as it could cause issues with libraries / dependencies - I think I remember Lior Pachter putting something about it on his Twitter but I can't find the tweet now. Is it OK to go ahead and upgrade, or should I still hold off? I really want to avoid bricking any of my code.
We have no idea what code is important to you. If keeping your code running is a priority (and this is your primary/only machine) then don't upgrade. Apple is generally good about keeping security patches supplied for prior version of the OS so you are covered there. I don't think Big Sur has standout features that make it a must have compared to Catalina.
That said I upgraded a machine in place and recently applied v.11.1 upgrade too. conda and environments are working fine. You could upgrade after creating a time machine backup. If something breaks after the upgrade, you can always go back to the last version by doing a restore from that backup. Only thing you are likely to lose is time/effort.
I second this. Big Sur doesn't break anything critical, but you will discover minor annoyances that will be like small pebbles in your shoe.
In my case, the OS tells me my 2-year old used-only-to-one-eighth-its-life battery is dead. It also has broken my DND scheduler functionality, which means my laptop gets notifications that wake me up at midnight unless I manually turn on DND every evening.
