I dunno if I'm looking for advice or kind words or what but something uncomfortable happened. I confessed to being polyam over FB and then a guy I have never spoken to said 'sup' and when I didn't reply he asked hours later if he could send nudes. After I said no he said 'I saw you were poly so I thought you'd be down.' I am supportive of all types of poly and know some are cool wit that but I am serious stuff only so my status being translated as automatically DTF was a bit disheartening.
Yep, that happens sometimes. And it sucks. People - in my experience, mostly straight men - often assume that being polyamorous means you are somehow obligated to pay them sexual attention, because the "sorry, I have a partner" excuse no longer works. It's a garbage mindset, and it leads people to behave in aggressive, obnoxious, and inappropriate ways. I've had this happen to me multiple times, including one especially scary brush with a man who would not take "no" for an answer because "I've seen you get cuddly with other dudes you know!" Gross.
The best way to handle this is to block and delete that FB creeper, because he was obnoxious and has no rights to your time or emotional energy. He can be out there being a jerk who is wrong about you and wrong about polyamory. Your relationship orientation/style/preference is NOT permission for random dudes to be nasty at you, and he was out of line. Feel free to set your boundaries clearly and not back down. Block, delete, remove yourself from a situation, do whatever you have to do to stay happy and safe.
People will make assumptions about you, especially if you're a member of any minority group - "women are like..." or "all bisexual people do..." - and it's miserable. Being openly polyamoroys does mean that people will ask intrusive questions and be generally unnecessary. But you are not alone! Find a polyamorous forum or support group where you can be yourself, and honor the courage and pride it took to come out as polyamorous even though certain people chose to respond in an awful way.