Originally Posted by
Robanker
I agree with J'onn and with most shapeshifters, though I do think that someone who becomes one need not necessarily become any more or less queer. As an example: if you're a lesbian Amazon and become a shapeshifter, it doesn't necessarily mean they'll no longer identify female and find women attractive and feel nothing sexually stimulating about others. I do believe it would be the cause of a lot of introspection and possibly a revelation about themselves, but not that it's a hard-and-fast rule that it happens.
J'onn, however, comes from a different society full of shapeshifters and the most recent origin indicates that they pick a gender identity (and shape) when they reach a certain age, so it stands to reason that J'onn could simply be heterosexual and masculine, but I strongly doubt it. With J'onn, like with Diana, I suspect that until now his more queer tendencies were simply off panel or subdued because he longed for a little of that acceptance that his friend Superman was so freely given. J'onn's a strong dude, but his family and race were exterminated and he's old enough to carry the baggage. I wouldn't fault him for struggling to fully be himself if he thought it would cost him companionship. Loneliness is very successful at making people compromise themselves to be rid of it.
I have a similar opinion on Starfire, who while it's possible she's straight, given what we know of Tamaran (or at least her perception of it through recollection), she's likely pan.
Clayface as a closeted actor is the best read on him. If that's gay, bisexual or more broadly queer then so be it, but ever since I saw that episode as an adult (it flew over my head as a child) I can't see him any other way and Alan Tudyk riffing on it with his performance kind of solidified it.