Manored i didn`t suggest to micro in that state. And it`s exactly not "hacky" because it is not meant to solve your specific issue, rather your issue is solved as a byproduct of that.
Switching between zoomed out and in let`s you be aware of the map as a whole, helping your decision-making, your awareness of eco, just how things relate to each other.
Ofc if you micro, you should zoom in.
Your brain has enough capacity to remember the radar-symbols in your example, so if you zoom in again you won`t find it that hard to differentiate your units.
I mean, yes i see what your problem is and that you can search for solutions to it. I on the other hand realized that i never had that problem in the first place and think it is because i see my units zoomed out (radar-symbols) and in constantly anyway.
So, if you are looking to improve as a player, your problem gives you good hints on what you lack. @CatMaster `s post goes into that direction as well.