For software issues they have a real person - me, and for hardware ones they can be sent to ANY repair service. Just close to them there are like three vendors who do hardware work. But the thing is, for last 5 years or so I do not remember they actually had some issue with their box. Things just work and updates do not overhaul your system out of nowhere.
[dead]
The major os updates on mac are entirely optional. They still do security releases for the other os's for a long time. This current mac I am on sonoma same as when I got it. That 2012 I kept on mojave. Its just the most polished unix os. The hardware is always set up to work perfectly with it. No driver support issues. Just works. Always works.