Ironically it's the very same things in Top Gear that was, that the haters disliked, that the fans of the show used to tune in & watch. Both my wife & I were entertained on many an occasion, watching it for what it was, a "pretendy" high jinks show. I can understand that some disliked the shenanigans, but seemed to go to great lengths to show their hate, perhaps making them feel better.
Clarkson was an actor & used any format he saw fit & offended people so much so it would seem that some wanted him dead. Aye the safety from behind the keyboard is a comfortable place. I've never met the man, but I've talked to some people who have & the message is always positive. He does quite a lot for charity & unlike others doesn't shout about it. I'm only making observations here. Clarkson was never short in sending himself up either.
As for Chris Evans, he is a different kettle of fish all together & being a petrol head is the only thing in common with Clarkson. Drink in his early career just about wiped him out. Now, I feel he can be bit manic, very highly strung & may come across as too much to watch for any length of time, even on a car show. Stating the obvious, we can only wait & see.