I lost access to so much cherished stuff that I am currently evaluating a switch to Ubuntu 20.04
Must have just gotten lucky, but literally nothing stopped working when I migrated to a new Catalina machine. Ok I had to do some jimmying to get Keybase back, but that wasn't a 32/64-bit issue, that was weird kext permissions stuff.
Pretty much 90% of my Steam games that had Mac versions, suddenly did not work. And there was no warning, because most of them weren't currently installed (so the catalina installer didn't warn); I just got a cross through them after upgrading.
"Mac gaming" wasn't something I did that much anymore, but I had a lot of attachment to certain games (some which of course "I totally intended to replay one day") and suddenly they became unavailable.
Many older apps I still ran now and then, stopped working.
I kept my S.O. on Mojave so that I wouldn't be forced to upgrade her Office suite to the subscription model Microsoft is pushing.
Etc.
I understand the frustration, though. Apple's spent the last 5 years or so dropping features I care about and breaking things important to me, across my iPhone, iPad, and MBP.