John Simon isn't a "hoot". He is a disgusting, venal, homophobic racist.
While he is very theatrically savvy and knowledgeable, he often used his column to attack peoples looks and make openly homophobic and racist comments. For those who don't remember, in 1985 he was overheard complaining about "Gays in Theatre" and hoping that AIDS would kill all of them off. When confronted he admitted that he said it.
There is a reason why he was fired from both New York Magazine and Bloomberg.com (Granted the firing from New York Magazine was 20 years too late). John Simon is living proof that the good die young.