If children are taught to use opposite sex pronouns it reduces my ability as a parent to safeguard them. I'm thinking about how differently I'd react to hearing the following from my daughters:
'That cleaner was getting in the way when we were changing for PE again. She's always mopping the floor when we finish PE'
vs
'That cleaner was getting in the way when we were changing for PE again. He's always mopping the floor when we finish PE'