What DM do you use? I have endless problems with scaling in both Gnome 3 and Cinnamon, compared to Windows where I've really never had a problem except with some very legacy software. The underlying problem is that the scaling setting in the WM tends to only be observed by software built with the same toolkit, so you have to set scaling up in a different way for each GUI toolkit and there's a decent list of them in common use on Linux.