I had minor bugs in macOS but nothing groundbreaking. Continuity works 99% of the time for me.Lucky you.. using Mac since 2006.
From Yosemite onwards it’s just a free fall. Bugs over bugs, half baked features, wifi disconnecting randomly, Mojave logged in without even typing a password when prompted, Catalina a disaster, couldn’t sync my iPhone reliably for 6 months through finder, I don’t know what you use the Mac for but it came to be unpleasant to me.
The photo app is a disaster, iCloud not syncing properly, continuity stops working as soon as you log in with a second user account and you must reboot to get it back up and running, sending a voice message with iPhone messages is stopping as soon as che display go on standby, so you can send a message just as long as your screen standby setting basically.
I don’t know what you use the Mac for but those bugs are just an everyday thing.
Not to talk about HomeKit, I don’t even start with that because I would go on for one hour
I use my Mac everyday and its been great so far. I NEVER had wifi disconnects on any macOS. My Mac for the past 2 macOS versions has be en working reliably.
I am sure there are people before Yosemite that had major bugs and I am sure there are people after Yosemite had minor bugs.
Just because its broken for you does not mean its broken for everyone.