I don't know. I think it's actually pretty rare for a genuinely dirty driver to turn up, and when they do, everyone thinks they've changed the sport. Because Senna and Schumacher overlapped, people do like to draw a comparison. I don't think it's necessarily fair. The fact is that that sort of thing used to be a lot more tolerated than it is now. Remember James Hunt's commentary when Prost collided with Senna at the 1989 Japanese GP? Hunt immediately called that it was deliberate and moreover that under the rules it was totally legitimate. Hunt 'The Shunt' was well used to a bit of 'robust' driving, after all.
But this was what Stirling Moss had to say about Giuseppe Farina, the 1950 World Champion:
"On the track, though, Farina was a b______d, completely ruthless — dangerous. And the worst of it was that he'd behave exactly the same way with an inexperienced guy. If he was lapping you, boy, you'd better make sure you didn't get in his way — he'd just push you off the road." Moss wasn't exaggerating. In the 1936 Deauville GP Farina did exactly that to Marcel Lehoux, resulting in Lehoux's death.
I remember everyone clutching their handbags about Senna's move on Prost at the 1988 Portuguese GP, but looking at it now, I honestly can't see what the fuss is about. Prost always had room. He kept his foot in and Senna straightened his line. Compare it with Schumacher's move on Barrichello at Hungary in 2010, where he actually put Rubens in the position of driving directly at an end-on concrete wall... To my mind, that move was so ludicrous, so potentially lethal that it should have resulted in an instant lifetime ban.
But Senna? Even the 1990 Japanese GP is exaggerated. A lot of the fuss about that is because Senna implied he would not back down if Prost failed to give him room - but he'd said exactly the same thing to Mansell at an earlier race, and hadn't crashed. It was just part of how he operated - if you could intimidate a driver into moving over for you before you even got into the car, then you'd already won. And this, I think, is the distinction. Senna, rather like Max Verstappen, put rivals in the position where they could give up the place or risk a crash. Schumacher didn't give them the choice, he just drove into them. He didn't learn that from Senna. Maybe from Prost...