Ten year olds may have crushes, but at least in my experience, they don't really have actual relationships. To me, that's more of a thing for teenagers. Middle school (12-13) at the earliest. I don't mind kids having crushes, and XY in general, games and anime, is a bit weird in that it seems like the characters are older than ever before (heck, in the BW games, the player characters are stated to be 14), but last we knew in the anime, Ash was still 10 just last season, and the thought of kids that young actually dating kind of makes me uncomfortable. I mean, when I'm shipping, I sort of AU it a bit, and pretend that Ash has been aging all this time, but since this is a discussion about canon....well.
True. And of course, generally speaking queer characters/relationships have to be exhaustively proven within the canon, and even then, you'll still have people deny it. And Ash doesn't even necessarily have to be gay--he could be bi, or a lot of other queer identities, and it'd be awesome for a franchise as big as Pokemon to finally give queer kids some representation, and to have the chance to see themselves and cute, innocent crushes when they hardly ever get to. As I said with cases like Shauna in the XY games, the franchise seems like it's opening themselves up to the possibility, which would be lovely.
And the beauty about Diode in particular is that we've already had examples of how Ash has interacted with boy travelling companions in the past (Brock, Tracey, and Cilan), and again, at least to me, the way Ash is with Clemont is markedly different. It'd be a good example of how attraction works, and that just because you're interested in this one person, it doesn't mean that you're automatically attracted to every person of that gender.
Idk, ultimately the anime is advertisement for the game series, and is otherwise aimed at children, and to teach them good morals (about friendship, compassion, perseverance in the face of adversity, pursuing dreams and goals, etc), and I feel that, in ships like Diode becoming canon, there'd be fodder for a lot of good life lessons, representation, and would further existing themes like tolerance and the like. *shrugs*