They hated him because he said that everyone is special, everyone deserves to be treated with respect, and nobody is inadequate. Fox News felt that wasn’t a good message because it made children “soft.”
Conservatives are awful people.
Don't forget that his "everyone" also included black people, as he illustrated with a segment where he invites his black mailman to share a pool with him and then washes his feet. That really pissed off a lot of "Christians" back in 1969, in post-Civil Rights Act America.
But then, those "Christians" are still the same way today. Just that they can't be as overt towards black folks anymore (though some certainly still manage to do so), so they find more acceptable targets.
As Bon Jovi said, "It's all the same, only the names will change."