Smartphones can't run PC games natively, which I personally prefer to smartphone games.
There are plenty of PC games that have mobile ports. All the GTA3 ingine games, several bioware rpgs.
You're confusing "can't" with "publisher hasn't bothered".
The hardware, certainly on newer iphones,is plenty powerful.
first, there were tons of x86 android devices. samsung tab3 to name the last one i used.
second, most of the code on android is tainted GPL code. technically GPL was supposed to not prevent you from running whatever you want on devices you own if it was distributed with GPL based code, but alas, that is exactly what happens.
It's almost exclusively due to technical reasons.
(tried to add as much as you to the discussion)