I have used a 4k screen for several years now without any issues on GNOME with 200% scaling.
However, I recently bought a ThinkPad T14 with a 1080p screen. With 100% scaling, the fonts and widgets are too small. The ideal scaling seems to be 125% or 150%. GNOME has experimental support for fractional scaling. This works generally ok for Wayland applications, but windows of X11 applications are incredibly blurry both on the laptop display with 150% scaling and the external screen with 200% screen. I think they are rendered at 100% and then scaled up. There are various workarounds for X11 applications, but it seems that e.g. none of the workaround really works with e.g. JetBrains IDEs (there are some bug reports about it).
Windows 10, on the other hand, handles fractional scaling and per-screen scaling just fine. It's frustrating, because I highly prefer GNOME and Linux and if all applications supported Wayland, there wouldn't be any major problems.
I have a similar problem with a QHD screen that I want 150% scaling. The worst part is that using the experimental scaling is it seems to consume a lot more cpu usage and thus power on my laptop.
14" WQHD would have the same problem, you would just switch 125% to 150%.
The ideal would be 3200x2000, but sadly, nobody sells such laptops anymore. Everyone jumps from WQHD to 4k. With 4k, you have exactly the same problem, except for 125% you need 250%.
In Windows, large fonts is basically 125% (120 dpi, vs the base 96 dpi, double for @2X HiDPI), except it enlarges only fonts and pushes dialog controls around, but doesn't touch raster assets. It is something that was part of Windows since '90s, but in many applications, it newer worked right, because the developers never knew about the option and newer tested it (looking at most Delphi developers here).
Changing scaling to 125% (since Windows 8 and 10) changes both font sizes, grid calculations in windows controls and bitmaps; the subtle brokenness of some apps disappears, just to be replaced by another set of subtle brokeness. However, the good news is, that the chance of developers testing in this mode is higher than them testing Large fonts.
I also have 1080p 14" laptop somewhere; at 100%/dpi the display is too tiny, at 125% it is great. I also used to have 1600x900 14" laptop (T430s) - that one, at 100% was perfect (except it was an TN display, which was different downside). Prior to that, 1440x900 (T400) - that one was a bit too large.
However, I recently bought a ThinkPad T14 with a 1080p screen. With 100% scaling, the fonts and widgets are too small. The ideal scaling seems to be 125% or 150%. GNOME has experimental support for fractional scaling. This works generally ok for Wayland applications, but windows of X11 applications are incredibly blurry both on the laptop display with 150% scaling and the external screen with 200% screen. I think they are rendered at 100% and then scaled up. There are various workarounds for X11 applications, but it seems that e.g. none of the workaround really works with e.g. JetBrains IDEs (there are some bug reports about it).
Windows 10, on the other hand, handles fractional scaling and per-screen scaling just fine. It's frustrating, because I highly prefer GNOME and Linux and if all applications supported Wayland, there wouldn't be any major problems.