YANBU, just because people are attracted to people of a particular sex doesn't mean they can't also feel entirely platonically towards people of that sex otherwise we bisexuals can't have friends or even just handle other emotions as they come up maturely and remain platonic.
It is questionable whether every person can have a platonic relationship with someone they're attracted to, some people are more easily led by their emotions in this -- kids including teenagers are often in this category while they're learning to work with these feelings, and with adults, it's possible more of those people who can't/won't are men who ruin things.
And here is a good reason why, just because you wouldn't act on it, doesn't make it OK. You can't be just friends with someone you are attracted to.
Some people can, just like some can be friends with someone who they regularly find annoying.
Emotions are just another form of sensory information. Some are stronger and cause instinctive reactions - usually the negative ones, but most are (or at least start off as) mild and we either screen them out, change our behaviour, or learn how to live with them as they pass through.
I've had friends where I was entirely platonic for a while, had a crush for a month or so, and then it passed. Some I've had where they've gone from platonic, crush, platonic, annoying/fine in small doses and then had it fluctuate between platonic and 'I wish all the best for you, but your annoying habit is driving me up the wall' (I very rarely have a crush on someone more than once).
Maybe it's because I've been rejected a lot so the idea guys always will rings hollow for me (or maybe I'm just that ugly and weird) or just my mindset, but I don't find it hard to enjoy a platonic relationship even when I have other fluctuating feelings, and I've learned how easily those emotions can fluctuate - at least for me. I've had strong crushes crash and burn with one sentence uttered, never to return. I'm not doing anything as drastic as this guy for something so fickle.
That some people do shite like hedge their bets like this guy has done or other nasty behaviour doesn't mean other people can't handle them better or be good friends with other feelings involved.