Even I'm not sure if this is canon now.
In any case, this is not a question anyone asked, but is inspired by questions that have been asked in a roundabout sort of way.
I've been asked a lot of times why there are so many gay and bisexual characters. The answer is basically just that that's what I default to when I come up with characters. I don't see heterosexual as the default.
In response to these questions, however, I jokingly considered whether magic had anything to do with the statistics found in Moperville.
Then I less jokingly considered whether having magic power made someone more attractive in any way.
The conclusion I reached was "maybe yes, but not in any earth shattering way."
And no, it wouldn't be like a love spell or something. Unless you count something like someone's face being symmetrical or smelling nice as love spells, but that's really low standards for love magickery.
That said, I imagine this being the case could result in more people being aware if they were bisexual. Not resulting in more people being bisexual, but resulting in more people being aware of it. So it could actually function as an in-universe explanation to some degree.
That said, you'd get similar results with the right fashion trends, soooooo... Yeah, I dunno. I just like the idea of stupid sexy wizards.