Before anyone downvotes this guy, spend some time on the official Apple support forum.

I can't point at a bug that I've seen addressed in subsequent OS releases.

Seizure-inducing HDMI flickering from Night Shift. Finder Trash not supporting put-back _sometimes_. Printers becoming permanently "paused" sporadically, or worse, very consistently. Mouse lag/stuttering because you used "the wrong USB port." Apple photos libraries corrupting themselves with no recovery paths.

It would be strictly better to just not have the forum, then shouting sorrows into the void would feel more solitary.

I hit issues in MacOS on a monthly basis, and have been for years.

Not once have I hit an issue that wasn't documented and left unresolved on Apple's for over 3 years.