Not anymore.
When I was in high school, no one thought I was anything but very straight... because my parents are pretty much bible-thumping homophobic bigots, I made a point of it to date as many guys as possible, so no one would ever suspect anything. I succeeded, despite having absolutely no interest in guys. Of course, the vast majority of people at my high school had no idea I had already come out as bi to my best friends.
At the first college I went to, straight out of high school, about half of people figured I was gay. I never said it outright, but the first couple girls I kissed went to that school, and I'm sure people heard about them... the first was pretty public.
I never wanted to be seen as gay, though. Or, rather, I never wanted to be seen as a lesbian. I started feeling that I might be trans when I was 18, but I didn't think then that I could do anything about it. Gradually, I tried my best to reconcile myself to the thought I was probably a lesbian. It never felt right, though.
I started identifying as one when I was 22... but I only ever told people I was "gay." It sounded better than "lesbian", since I definitely didn't see myself as a chick who liked chicks. The funny thing is, every lesbian I met told me I wasn't a lesbian. Maybe they saw something in me I couldn't even see.
It's been at least a year since anyone assumed I was gay... now I'm just a guy. It's hilarious, because since T, I've actually been attracted to guys. Guess I never was even a shred of a lesbian.
SD