Yeah, it's a guy thing. Women who self-identify as poly are probably perceived by most unaware guys as "easy" and so get a lot of attention. Guys who self-identify as poly are probably perceived by unaware women as "cheaters" and are shunned.
Personally, I would always put my true relationship situation clearly in an online profile. Always. Misleading someone, even if only by omission, is exactly the wrong way to start a relationship. I applaud your honesty.
I did meet an activity-partner online, but while I like her a lot I am very wary of getting intimate with her. She has been dreadfully hurt by men in the past and I simply will NOT be someone who she could ever suspect of using her for sexual purposes. So I'm the best just-friend that I can be.
Good luck with your searching. It's process. Life is never static, is it?