Linux user here, also once upon a time a Windows admin. I think the most difficult thing for most users is not that Linux is difficult, but that it is different.
Take Pop_OS for example. For the average "I check email and surf the web" user, it works wonderfully. But most people grew on Windows or Mac so its just not what they're used to. Linux is kind of the stick shift to Windows and Mac's automatic transmission... its not hard to learn, but most folk don't choose to make the effort because they don't need to.