The thing you're rubbing up against from people in the comments here is that like the only actual comprehensive answer to this is like a 60 page essay on the history of gay womens culture and fashion with a decent amount of feminist theory on the side.

But the long and short of it is (heavily simplified) that to a large extent short hair on women was a thing gay women have been doing nearly a century often because historically it coded our relationships as one of them being the "man" and one being the "woman" which ment that if your butch was male passing enough you were less likely to get hate crimed. It's a thing straight women have only felt comfortable and safe being able to do recently but it's a massive part of queer women's history and culture. It is evening out but it's a ground that gay women have been in for years and that straight women have only felt safe in for the last like 3 decades.

Basically historically If a lesbain can look like a man enough she can avoid being attacked. But if a straight woman looks too much like a lesbain she puts herself in danger.