The Macs and iPads have their own problems, but nothing like that.
https://ubuntu.com/about/release-cycle
The 16.04 is still supported and it was released in 2016! So it must have been an even older system, right?
The moment it runs an update all bets are off. It's always audio for me, it breaks in the weirdest ways.
Mac updates are the best in the industry, period.
Close to zero chance of having an issue (unless you're messing with third-party kernel extensions).
There were millions of other annoying small things in Ubuntu itself as well. I’m sorry to say but as much as I love nix systems Ubuntu wasn’t really for general public - maybe it’s better today, not sure. Heard the story over and over again - that it’s superior, and every time I try it I’m utterly disappointed.
The key with Linux was giving them an LTS Ubuntu but not messing with it at all.
The problem with macOS recently has been that it keeps changing how things work which would result in the relatives messing around and messing up the system.
Ubuntu has been pretty rock solid and reliable, while not changing anything drastically enough to lead them to try and mess with it.