I’m happy you sent this ask, because it’s a perfect place to talk about how someone can get hurt, feel wronged, and become susceptible to extremist recruiting.
First off, treat this as a simple yes or no question, asked with zero surrounding context, the platonic idea of penis preference if you will. “I don’t find penises attractive” is not a sentiment that makes you a TERF. You’re okay not liking them. My nonbinary wife doesn’t particularly like them, yet they are married to me (who has one) and we love each other more than anything in the world.
In fact, in the abstract, I don’t like ‘em much either, and I own one! Ridiculous looking thing, wish I didn’t have to deal with it. A general dislike of genitals doesn’t make you a TERF… not by itself.
Now, here is where the critical thinking comes in, because if you posted something like that on Tumblr or something, it has a different context. You might not even know! It could be a totally innocent mistake, and it happens, and some women either get criticized in ways that makes them feel attacked, or actually attacked because you never know if what you post online is hitting someone on a bad day or a good day.
The context first of all is, without any clarifying statements, saying you don’t like a genital could imply you’re reducing anyone with that particular set of genitals down to their genitals only. And it could result in either someone telling you it sounds TERFy (if they’re trying to be gentle) or calling you a TERF (if they’re out of spoons) because that’s what TERFs do. Here’s where it becomes a recruit pitch.
You say “I don’t like penises.” This doesn’t mean you’re saying you dislike trans women (not all of whom have penises anyway), but if you get the above lecture/yelling, a radfem can come along and empathetically agree how unfair it is that someone made you hurt for saying you don’t like a genital, and it’s not fair to tell a lesbian she has to sleep with a male or she’s a TERF and- OH WAIT A MINUTE!
Hold up, it looks like they were just being nice but wait wait, they just slid cozily from “it’s okay not to like a penis” to “anyone with a penis is male.” See that? Like a sleight of hand, once you’ve agreed with that premises, saying “I don’t like penises” suddenly becomes attached to “and anyone with a penis is male.”
Alright now in context, going back this kind of equivalency is so common with radfems that at this point saying you don’t like a genital is what we call a dogwhistle. It’s a phrase which is seemingly innocent, and can be innocent, which has been so widely appropriated by a hate group that it carries extra connotations in a certain context. Contexts like posting on Tumblr, which happens to have a particularly large trans population.
Now you can’t know every single dogwhistle because that’s the whole reason they exist - so normal people don’t spot someone’s bigotry and it looks like a disenfranchised group is getting angry over an innocent statement.
And lastly, which you probably already know, but generally not being interested in something doesn’t have to equate to disliking anyone with that trait, or even not being attracted to someone with that trait. I bring this up because the difference between a lesbian who just generally doesn’t like genital and a TERF is that the TERF things anyone with a penis is automatically bad and a male and probably reading this right now thinks I’m saying you have to have sex with men or like penises, somehow, despite saying exactly the opposite.
You may have a general preference, but in practice I’m sure you’ve already found a difference between “I am physically attracted to how this person looks” and “Holy shit I am in love this person is amazing and everything about them is beautiful.” If you haven’t had that experience yet, I can promise you some day you will. Not necessarily over genitals, but some day someone will come into your life and you’ll love every part of them whether or not it’s something you normally find abstractly attractive.
Keep your heart open to love, keep your mind open to constructive criticism, and you’ll never be a radfem or TERF or SWERF or whatever. That’s all.