Having set this up, this is going to be absolutely huge for ML. A lot of nonsense is getting cut down by this: 1. You don't have to install special CUDA-specific drivers that are behind the normal gaming drivers anymore. You'll soon be able to just use the Regular nVidia Drivers (and even now, all you need to do is install a Beta driver version). That's huge for someone just starting out, they don't have to have "the…
The picture is more mixed than you present.
I use Fedora at 2560x1440@14" and 2 by 3840x2160@27 and the dpi thing isn't an issue, set your font scaling to 1.5 and that's about all you need to do.
I dual boot windows and fedora (for gaming in the former and dev in the latter) and Windows 10 is by far more unpleasant to deal with, updates that tie your machine up for significant time, drivers are still "track down random binary from random vendor site and hope it works" vs "sudo dnf update" is (for me) no comparison at all.
Into the territory of personal preference, Cinnamon is a better desktop on than Windows - it's more responsive, more cohesive, closer to the classic WIMP interfaces I prefer.
As for wayland, I don't use it yet, I will when it's been stable for a year or two.