Do average users want to, and are they capable of, properly administering an OS like Windows?
Yes. Turn it on. Done. Administered.
Microsoft has dumbed it down to that point for us. Updates? It'll work itself out. Viruses? Just hit the refresh button if it goes tits up and windows defender can't fix it. Backups? You mean your files weren't on Onedrive?
Seriously if you're "administering" a windows machine without being paid a salary to do so then you're doing it very wrong.
We'll have to agree with disagree. My non-technical Windows-using and macOS-using friends get themselves into trouble all the time because taking care of their Windows and macOS systems is far too hard for non-technical users.