A lot of people in the fighting game community would disagree, but I noticed that it really doesn't make a difference. Pros will still stomp noobs.

Marvel vs. Capcom 3 and its upgrade had a very simple control scheme: three attack buttons and a launcher. This is different from what you are talking about, but it still doesn't stop Justin Wong or somebody from utterly destroying other players.

Games like Persona 4 Ultimax, Marvel vs. Capcom, and Blazblue have offered what you are talking about, and there are limitations involved in such a thing, too. Like....not being able to use certain attacks or certain functions of the gameplay engines. This balances things out and still will not let a newer player who's been playing all of 5 minutes beat a more skilled player.

CvS2 EO (EO is for Easy Operation) is a bit different in that the gameplay functions weren't limited as far as I can tell, but still, any decent player can beat someone who is using EO. The people who were complaining back then only did so because the game was still fairly new at the time, and plus, most tourney players didn't really delve into CvS2, anyway.