You take the high road, I'll take the low road.
The 'sheeple' will follow the path of least resistance, the easiest road.
Apple have managed to make their brand and easy road to take, at least for many, compared to both windows and 'Linux.
To choose 'Linux, you either need to be running too or desperate to run from the alternatives. Most people don't care enough. Enough phone operating systems have been given the ol' yeller treatment because they failed due to lack of apps people wanted, so restricting to UWP could do the same damage to windows.
The Windows sear might be uncomfortable and annoying, but not enough to force them out of the familiar comfort zone. The Windows seat has been getting increasingly uncomfortable for many since 7 is being phased out, but it's still mostly techies complaining.