Lucky. I'm currently on a 20.04 install with a 1080p laptop + 4k, and the scaling options are 100% or 200% for a monitor with fractional scaling I can apply with tinkering that applies to both at the same time. I just sort of have it in a non-optimal for either monitor state but I'm sure there's some way which I didnt find when I first installed it to make it okay. On a different machine and combination of monitors I've gotten it to work but with a lot of xrandr tinkering instead. I'm hopeful that your comment might suggest that next time I upgrade it'll work out of the box.

Ubuntu's upstream and release schedule ensures that its packages are relatively out of date. It might be worth trying 21.04 for real fractional scaling with Wayland or a different distro with recent packages and Wayland.

You're almost certainly right, as far as I can tell it should be fine with Wayland and 21.04 but I am just tired of reinstalling my OS every 6 months and don't trust direct upgrades much since they lose me even more time diagnosing an issue in the cases where they do break something.

I've upgraded a few of my systems from 20.04 to 21.04 without an issue. If you take a btrfs snapshot before upgrading, you can roll back the changes if it turns out there's an issue with them.

It's not lucky, it's just that I know better than to install Ubuntu. Ubuntu's been a bad choice from the beginning and intentionally goes against the defaults of upstream providers. Random corporate distributions never know better than upstream.

Ok, that's fair. Maybe I'll finally decide that Ubuntu has more drawbacks than advantages for me (and it does have both) and finally switch to Debian directly.

This is more than basic functionality, but I'm experiencing limitations with multiple monitors that I don't get in Windows. The bundled remote Screen Sharing in GNOME does not work in that setup. VSync (on NVidia, possibly not a driver issue) doesn't work well, resulting in tearing in one consistent.