The two most well known things about the franchise are the ridiculous boob physics and the 'volleyball' spinoffs.
Nobody says about Mortal Kombat "oh the violence isn't the game's doing, it's you who decided to kill the other guy"
Yes, if you are looking only at surface value then jiggle physics and spinoffs exist.
Jiggle physics exist in any game, though. SFII Taki is the best example. But soul caliber isn't considered the same as DOA, despite probably having more titilation per female member than DOA does. Its a matter of poor perception, nothing more.
Thats because MKX is literally DESIGNED around violence and gore. Its not a byproduct, its a direct part of the engine. If you removed it, it ceases to be MKX. They even hyped up the fact that this is the goriest most detailed MKX. When interviewed, thats the highlight, the part of the game they pushed more than any other.
Jiggle Physics just kinda happen in DOA, but if you removed them its still DOA. It wouldn't suddenly be less impressive if Katsumi didn't bounce when she moved, but if you had an MK game without fatalities in it, it wouldn't be the same thing at all now would it?
Don't confuse a necessary part of franchise with an infamous byproduct of an engine.
Akira isn't even near the top of the tier list. That honor usually goes to Ayane, Christie, and Genfu. Akira is high at best, at least in Japan last I checked, but lower in US tier lists, where the game is considered more developed over Japan.
His position isn't the issue, its the fact that he is a scrub-buster in the right hands on top of still being a viable threat. I'd wager on people getting tossed out of pools by an Akira before I would a Christie, but thats just my perspective.
Akira is the gatekeeper. If you can't pass, you don't deserve to win.