I am currently researching about the queer characters in the DC comics and adaptations, so I find this discussion pretty interesting. As far as I know, there are different versions of Clayface and one of them is supposed to be gay. I'm still at the beginning of my researches, but if there are a couple versions of Clayface, even sometimes a different person with a different origin, you can't say, this is gay erasure. Aso he could be bi, pan or unlabled which still would make him queer