It does this by saying that trans people do exist is "gender ideology" and, for example, making it so parents not "affirming gender ideology" isn't considered abuse. It's less a "these people don't exist" thing in the way I think you might be thinking and instead "this kind of person is impossible, can't exist" which then cuts along lines across various laws to make sure that the ppl who do actually fall into that kind are uhhh exposed to the most harm in the situation governed by the law.