That US fighting games spawned from MK says it all. When MK came out, it was huge with kids (including myself) and casuals, but was universally dismissed as shit by fighter fans and reviewers (reviews - in actual printed magazines - were a decent measure of quality in 1991). The problem was that while it looked incredible, every single character in MK played exactly the same, except for their 2-3 special moves. Same speed, hit for same amount, same endurance, no advantage/disadvantage in offence or defence, and (special moves aside) no difference in whether they were good at short v long range. It was also vulnerable to 'special move spam', where you just keep on spamming the ranged move. Still fun for me as a young teen, as those moves were both pretty and visceral, but very very casual as a fighting game.
Compare SF2. The special moves aren't 'win-by-spamming', but merely additional attacks to be used situationally (some characters favour minimal special-move use). Each character differs in how strong their defence is compared to offence (e.g. Blanka is all-out offence, Dhalsim is all-out defence), in their speed, how much damage they do, whether they're best at long-range or short-range (it's quite deliberate that Chun-li has no fireball attack and can be hit when she tries to spin-kick across the screen, while Ryu can fireball with impunity and Dhalsim has no close-range power attacks), and how much their blocks reduce damage. Even their basic moves are all completely different (Blanka's short-range bite-combos, Dhalsim's stretch-those-arms-across-the-screen, Ryu's generic balance, Sagat's push-them-from-short-range-to-the-middle-to-open-them-up-for-the-uppercut).
Yeah, I spent too much of my teenage years stoned in front of a computer screen. Come to think of it, the period during which I smoked marijuana (14-17) syncs up perfectly with the period in which I was playing console games at friends' houses instead of the monocled playing crpgs on my PC (played the shit out of wizardry and ultima as a kid, but abandoned the genre during my teenage years).