I am aware of the reality that banning trans people doesn’t stop abuse.

It seems like you’re talking about something different. Originally, you were talking about cis people who thought banning trans people would stop their husbands, etc., being abusive. In other words, that banning trans people would stop all abuse. It seems like what you’re talking about here is something different: not all abuse but only some abuse.

the people who genuinely believe this may react upon learning their problems have not been magically solved

Why do you think there are people who believe that banning trans people will stop all abuse?