If you find that once doing scaling on a computer with a HiDPI screen running Linux, everything works fine except Zoom, try editing ~/.config/zoomus.conf and make sure you have “autoScale=false”.
Credits to a Reddit post for this. HiDPI on Linux is still a bitch at times. Not sure whether Wayland in future will work fine out of the box. We'll see. On the other hand, Kali Linux's kali-hidpi-mode works VERY well with HiDPI so it's probably how some distributions handle the scaling.
