Eventually things get weird, you have to drop into the command line to sort it out.
Normal people have other interests, they don't want to invest 4 hours into figuring out what why their Bluetooth isn't working.
The vast majority of folks won't even want to install a new OS.
This isn't too much different from how a lot of people use Windows and Mac, many wil have their kids figure out how to setup an application for them. It depends, of course. A lot of professional apps just don't have suitable equivalents for Linux and WINE doesn't do it for them.
She doesn't play video games or need much space. An M2 MacBook Air is 800$. If anything goes wrong, just take it to the Apple store. Even out of warranty if it's something simple like you broke a setting, they'll fix it for you.
It'll be much easier to just buy a Mac. I personally don't want to buy a new Mac because I want to have a 4 TB SSD and to get that in a MacBook you have to spend between 3k and 4k. Vs being able to upgrade a cheaper Windows laptop for 200$.
I personally dual boot Linux Mint and Windows. Linux is much better for getting things done.
When you think about its main competition it's a little silly to keep framing it this way, but again, it's extremely effective so it doesn't really matter if it's right.