I use a 27” 4k monitor, in unscaled mode, but I use zoom heavily on macOS (Ctrl+Scroll Wheel) - with some extra scroll cruising setup with SteerMouse on my mouse. The lets me reduce the pixel to density to that if a much larger screen on-demand to help with my eyes a bit.
The one thing that I dearly miss from OS X going to linux, is the 'double tap to zoom on a text container' thing that simply doesn't appear to have an equivalent on linux. Being able to double tap and zoom up on text when I'm tired after a long day is very nice.
