I think I heard a trans man saying that this form of transphobia (erasing trans man) is rooted in homophobia :

From the POV of men :

• you meet a girl, and suddenly she has a ~~sick~~dick so it is gay because dick.
• You would not hook up with a guy, even if he has a vagina because you don't know in advance.

Now for the POV of woman :

• terf exists
• trans men are traitors, they just want to enjoy patriarchy so they should be forgotten.

At least, maybe trans men can enjoy this legal stuff, contrary to the island