AMD APUs are not that bad anymore, I am certainly considering a 3000G for my next cheap build. Obviously it would be nice to have a 15W Zen3 APU though, but one can only dream.
They aren't Zen 2, more than 4 cores or 7nm, all of which would make a huge difference. Putting the APU on the same chip makes them more difficult to cool, especially since they don't have quite as high quality packaging as the better CPUs. Getting smooth 4k realistically means messing with bios settings to get them to throttle less and run hotter.