So in an old thread from 2016...after reading miles of comments millions of guesses, about millions of unrelated things and about old versions of MAC OS and PS, someone said they simply use space bar together with the Fn (Function Key).
So I tried it.
this worked for me too...so weird, of course you can't really press the function key and the spacebar with one hand on a full size keyboard and use the mouse at the same time (at least not very easily) so I thought this was a useless solution. BUT, now it works, with just the space bar!!!?! WHAT!?!? ...it's like it just needed it's little Adobe brain woken up.