I always found that the Mac store did better than iPhone/Ipad to be honest, more downloads for paid apps.
It might be as there is not as much released on there so you are noticed more??
It was a bit of a headache at first trying to sort it out not knowing what I was doing using Xcode, however once you get used to it, it is ok.
I did a bit of a tutorial here a while back but it should still be valid to get the Tier 1 game onto the Mac store.
https://forum.thegamecreators.com/thread/215918
Not sure about getting the Mac version on the steam page though? Never done that and would be interesting to know if you find out.
The Amiga and Amos were great!