Terrible reasons ppl have theorized for why you're trans?

When I say terrible reasons I also mean silly reasons, just any explanation someone has come up with to explain why you're trans other than "your assigned gender at birth and gender identity are different".

For me it's something I'm not quite so hurt by anymore, it's more just something I find so absurd that it's almost funny. When I just came out as a trans man my mom asked if I thought I was a man bc I had an absent father and later insisted that must be why I'm trans, which is an argument I've heard about all kinds of queer identities. It's like one of those things that ppl are like hm makes sense psychologically, without ever actually thinking it through about how it makes absolutely no sense. And for the transphobic armchair psychologist ppl they could say something about penis envy (look that up + Freud if you think I'm making this term up) but that is also bullshit and nonsensical