'Crossdressing' serial killer

I've watched and listened to a bunch of true crime content about serial killers. Something that I notice gets brought up often is when they 'cross dress' or 'dress up like a woman'. It gets mentioned along with behaviour thats deemed degenerate that are red flags about their evil nature. I always found it strange, but assumed there must be a connection between psychopathic behaviour and having a cross dressing fetish. Now when I think about it with the fact autogynephilia is proven a myth, I don't think that there is a connection. I feel like a lot of transphobes and people in general however tend to connect these things, which adds to their belief about trans women being degenerate sexual predetors, and this kind of media portrayal doesn't help.

Am I right that this is just pure transphobia in these documentaries and other true crime media? Or can it actually just be a sexual fetish in some cases?