People complain about mixed DPI all the time on macOS and Windows too. It works better, but it still doesn't just work. If you want things to just work, you'll have less fiddling to do if you get similar DPI monitors.
Well, I think that saying works better is an understatement.
On windows I just plug my external monitor with regular DPI and it auto-recognize that this external monitor have regular DPI and size it acordingly while keeping the HIDPI of my laptop perfectly untouched and also auto recognized.
While on xorg, goodluck with that.
On Wayland it works, but require manual intervention of enabling fractional scaling and setting everything manually.
