Can't go to previous track when "autoplay" is enabled in Apple Music. Clearly an intentional choice. Works on iPhone. But on Mac it doesn't "just work". Syncing my music library with Apple Music doesn't "just work" anymore either. Some albums are visible, but are greyed out and can't be played. Time Machine hasn't "just worked" in several years - would corrupt my backups and have to re-create from scratch every week or so, I've switched to Carbon Copy Cloner. Non high-DPI displays don't "just work" anymore. The forward button in Finder, the icons in Music settings, all squished horizontally like it's someone's first time adding clipart to a Power Point. Safari stopped "just working" with 26.0, now opening a new tab or typing into the search bar randomly presents me with a 1-5s delay - or sometimes the whole thing hangs. I could go on, I don't dare upgrade to Tahoe - it's death by a thousand cuts.

Edit: LOL, how could I forget Siri. I don't use it often - generally only in the car to switch music - but it's terrible at understanding what song/album I'm asking for. Tried repeatedly to get it to play the "Mob Song" from Beauty and the Beast and I got some death metal instead. Completely useless.