I don't think that's what's being argued. Diversity within and between genres can only be a good thing. But Sonic's mechanic was fundamentally conflicted. A game which moves super-fast and then puts unavoidable obstacles in the way is just frustrating.
I can think of two very different games which strike the balance much better than Sonic ever did. Rick Dangerous was a platformer which was littered with often invisible and unavoidable traps which killed the main character instantly. But speed was not the goal. Pixel perfect positioning, perfect timing and memorising the layouts of the levels and the traps was the only way to succeed. It was often frustrating, but at least when you failed you knew it was your own fault after the first time you fell into a hidden trap. It was almost a cerebral experience.
In contrast, the Donkey Kong Country series (and in particular DKC Returns) provides an exhilarating thrill-ride without any of the hidden danger or insta-death frustration. Levels like Barrel Canon Canyon, Mine Cart Carnage and Snow Barrel Blast allowed you to whizz along at great speed without fearing an unavoidable death trap where you inevitably land. This was because there were no unavoidable death traps in these games. The beginning of a speed run was controlled by the player (e.g. the timing of a barrel blast) and to a certain extent so was the trajectory, but you always knew that the game would not be cruel enough to throw you into a trap at the end. That meant you could enjoy the ride and catch your breath at the end before the next part. DKC Returns took this to the next level with 2.5D, meaning you could blast through huge tree trunks, temples, pirate ships and more, all at great speed.
Where Sonic went wrong was trying to be fast and dangerous. The combination was exciting for a little while, but annoying for a long while - exactly the opposite to how gaming should feel.