One thing that's for certain is that I made things very hard for myself by using a hidpi monitor, but it's actually very difficult now to buy a laptop that isn't hidpi!
Some people have claimed the problem is not hidpi per se but the fact that 150% DPI, "fractional" DPI, is a big problem on Linux, but this too confuses me because 150% DPI has been bog standard on Lenovo laptops since 2015 (and, on Windows, entirely Not A Problem) and CW says Lenovos are good for Linux. So WTF.
My conclusion from installing Linux on a Surface tablet is that they *also* did not really consider the mode where you have a touchscreen and no keyboard plugged in, because it has the same problem. There was seemingly no way to get the onscreen keyboard to show up only when you interact with an input, and a lot of apps didn't seem to support scrolling via the touchscreen.