Is this toxic /abusive

A friend of mine caught her fiance (they have been together 12 years) masturbating in thr bathroom. So now she has made it a rule that he cannot bring his phone into the bathroom with him at all anymore.

I told her while it's none of my businesses, I find that really controlling and abusive. People need privacy sometimes, people deserve to touch their own bodies. She thinks I am wrong.

What do you think?