This is what I usually do. I run 4k at "100%", but then I increase font size as needed. I usually don't care about the icons, widgets, etc since I rarely interact with them, so to me, it's actually a good thing they're small. This way everything is plenty sharp, and I also get more screen real estate.

The reason I use a 4k screen is to have sharp text, so I try to avoid scaling.

That’s why – despite being a free software advocate – I currently run Windows for all critical software, as on Windows I can scale content without re-scaling windows. (Qt and Android support it as well, but Gnome and macOS don’t).

I'm not using Gnome, but scaling the text works fine for GTK apps on I3.

Yes, but Elementary, Android, Windows and Qt can scale icons and all elements together with the text to any arbitrary scale, pixel-perfect, without any post-processing.

GTK can only scale text, or scale the whole window to 2x, 3x, etc and then scale it back down in post-processing.