"It frankly astounds me that Apple, a company that was and still is considered by the industry the pinnacle of stable work tools, did not care to test their products in environments where they will be used"
Pro audio gear is notoriously slow to change; products stay on the market unchanged for 8-10 years or more. Many (anecdotally, I'd say most) pro audio interfaces on sale now -- including some relatively new designs -- use USB 2.0. Why? No clue. But for whatever reason, there's a shit-ton of USB 2.0 audio gear in stage and studio rigs all over the world and Apple should make it their business to know that. FWIW, I have never seen a Thunderbolt or USB-C pro audio device in the wild.
I have Apple products, but mostly because they are not other things. I'm typing this on a MacBook Pro -- because it's the only* way to get away from the Windows 10 slurp and forced updates. I have iThingies, mostly because it's the only way to have a smartphone or tablet without the unblinking gaze the Google or Amazon panopticon.
Apple's hardware and software quality were never perfect, but they have absolutely cratered in recent years. Butterfly keyboards, free 'root' logins for everyone, the Group Facetime faceplant, a new massive Keychain security fail, the ongoing saga of iOS 12.x updates breaking cellular and WiFi, hockey-stick-shaped $1000+ iPad Pros, ThrottleGate, the entirety of iOS 11. The days of Apple products displaying the quality that is expected at their premium price are long gone.
Apple supposedly has 132,000 employees, but I can't for the life of me imagine what most of them do all day. It's obviously not QA testing or code review.
* I tried to make Ubuntu Studio do something useful in a music context, but the very, very short list of supported audio hardware did not include anything I own. Also, JACK is an abomination.