My go to example would be long lasting issues with SMB support in Finder. All operations are very slow, the search is almost unusably so. The operations that are instant on every non-Apple device take ages on a Mac. I first ran into these issues 7 years ago when I set up my NAS, and they present to this day. I tried all random suggestions and terminal commands, but eventually gave up on trying to make it perform as it does on Linux.
With Apple's focus on cloud services, fixing the bugs that prevent the user from working with their local network storage runs contrary to their financial incentives.
Finder is genuinely horrible. It’s obvious no one at Apple cares about files anymore nor anyone working with them.
We’re all supposed to consume cloud these days or so it seems.