Marvel has been putting things like that in as in-jokes or slash fantasy fodder for decades. Scott Lobdell, Fabian Nicieza and Mike Carey have all admitted to doing it for those purposes, among others. It's a lot like with the TV show Supernatural. The show's writers and creators know there's a segment of the fanbase that like to see Sam and Dean as gay, and ship them together as a couple, or Dean with Castiel, or Dean with Crowley, or Dean with damn near any guy, lol; so they put stuff into the show to play to that.
The problem with making that fantasy a reality is two-fold. One: Most of the people watching the show don't see the characters that way, and more importantly don't want to see the characters that way because it would interfere with the way they currently enjoy the show. Two, most of the people watching the show wouldn't find it believable if they did make that change because to get there it recognizes a few almost-trees that were never clearly even real, and ignores a really massive forest that is. It's much the same with Iceman. I've read pretty much every appearance of the character. Original X-Men, Early Years, Hidden Years, The Champions, The New Defenders, X-Factor, Current X-Men, mini's and one-shots and guest appearances...For every thing it would fit with or explain, it would conflict with and contradict dozens and dozens more. It focuses on a little and glosses over a lot.
I'm not saying Marvel couldn't or wouldn't make Iceman gay, they can make any of their characters anything, and find explanations in this panel or that panel for all of it. The question is would it be believed and would it be accepted. With decades of comics, cartoons, movies and the character not depicted that way, it would be a hard sell for a lot of people. I think a lot of fans would be better off just enjoying their fantasies as fantasies instead of waiting, even expecting for something in their head to actually come true. Once you start getting your hopes up for something like that, and it doesn't happen, you're opening yourself up for a lot of disappointment.
I think a lot of that is part of why the boards here got so bad, people talking about "head cannon" and treating their own fantasies or personal viewpoints as authentic, and trying to force that on other people, and even to an extent Marvel itself; to the point of attacking writers when they would post here. And for the record, you didn't come off as remotely trollish, you were very respectful, I hope I manged to respond in kind.