Here's what I'm going to say here. With Windows it's very easy to make it a very slow running/system with problems. But, it's generally quite hard to entirely break it such that you cannot get to the GUI and attempt to fix it.

With Linux, just updating will sometimes break the system to the extent that if you're lucky it will boot to a terminal. I'm experienced with linux (since the 1990s) and I've had linux systems that took my a better part of a day to fix. Someone that just wants to turn it on and work is going to be lost trying to fix this kind of thing.

Ubuntu upgrades from one release to another are extremely hit and miss in my experience and again if you don't know how to pick up a failed upgrade and complete it, then fix the broken dependencies, fix the upgraded stuff that doesn't like your old config files, etc etc. You're going to be in trouble.

Linux is objectively better in every way except when it goes wrong. This is one of the reasons normal users won't adopt it en-masse.