Which is reducing the complexity of control schemes to either nothing or mortal kombat like combos.
Forward, down, forward, high punch to build a new city in a 4X in a few years?
If, as you suggest, the control schemes of video games are becoming less complex (Forward, down, forward, high punch) then surely the result would be more games that are playable with only a keyboard, not fewer?
It was back in the days when we gathered at the kid whose keyboard could actually support so many simultaneous keypresses and did tournaments.