We have the same problem here in Germany with that kind of thinking.
While there is only a small minority of people who demand that everything has to be politically correct, the problem is that many decent people are afraid to speak up against their demands.
The reasons why so few women decide to become a firefighter has nothing to do with fireman Sam, but with different preferences of men and women. By the way my daughter likes fireman Sam very much and I can not even imagine that watching fireman Sam will discourage her.
Fireman Sam is the opposite of what the SJW call toxic masculinity. That could be the reason why they hate him. Sam is a decent and brave man, he is strong and devoted his life to rescue and help people.
The tickler is the brigade call their crews fire-fighters, not firemen any more, so they could have called him/her "Fire-fighter Sam" and as Sam can be short for Samuel or Samantha its completely androgynous... all this crud could have been avoided.... complete cocks the PC brigade