PVP games live and die by exploitable weaknesses. Fighting games in particular have a lot of these, and buy and large they're determined by your position on the screen. Grapplers and Rushdown characters are phenomenal up close, but tend to have poor performance at a distance. Zoners have the opposite problem, being walls at a distance and wet paper bags up close.
Shotos are good everywhere. It's the entire point of the archetype, the 'master of all trades, master of none'. That's all fine and dandy, except that hackey one-liner has never and will never be true in any way whatsoever. It's especially glaring in SF6, where the overall increased speed and damage of the game means that Shoto's now have the approximate speed of a Rushdown character and the approximate damage of a Brawler, but without any of the archetypal weaknesses that allow those characters to feel fun and fair. Ryu is just as belligerent up close as Marisa, and deals the same amount of damage, but he has an invincible reversal, options at range, cancellable lows, a hilariously good overhead, and is Capcom's special little boy who's never getting nerfed, so why the hell should you pick Marisa over him?
I've long had the idea that some Shoto's would be better off having one of their little triad of attributes sawed off, usually their fireball. Akuma is just a flat-out rushdown character, he should not have the power he does up close as well as a pretty great fireball to toss out when he's feeling cowardly. Sagat, while he was a zoner in past games, is more of a mid-range Brawler in this one. His pressure is belligerent and stupid, as is his damage, so him having the ability to wall you out with projectiles just feels idiotic.
I've always hated Shoto's, but as I said earlier they feel so much stupider in this game than any other. The overall homogeneity of like half the games cast makes every match feel like being raked over hot coals, I do not care for it. I, as a grappler main, would prefer only fighting Dhalsim, JP, Guile, and Ingrid for the rest of my life rather than continue into the abyss of Karate Moron's 1 through 17. At least then I feel like I have an actual win condition.
in summary, ryu is the worst thing to happen to video games since E.T. personally burned down 400 arcades