Yeah, I thought maybe the Trump supporter was questioning Biden's sexuality by insinuating he's bisexual or something. But your interpretation makes more sense, since it would amount to the supporter's aping of Trump's mockery of that disabled reporter.
Monkey see, monkey do when it comes to cultism. So what do we do when a cult goes mainstream?
Good point about the anonymity too, since that's consistent with the alt right's penchant for mere trolling.