This question is an oddity because it assumes something that's probably not the case. But I don’t think it belongs in AGM necessarily, for several reasons.
Firstly, the question is along an ethnic (white/Mexican) more than sexual identity (gay/straight) axis. It addresses the preference of white men, rather than gay men. So it's probably not all that relevant to non-white gay men posting in AGM. But equally it could be relevant to bi men, and actually also to the many many straight-identified men on the site on who take an interest in cock. Witness the literally tens of thousands of posts in the webcams section for Str8 to straight cam/Skype/jerkoff from men not identifying as gay. So it's simply not the case that only gay-identified men could have an interest in this question or be able to answer it. It could go in Ask a Man potentially for a wider audience. But it is an oddity so better here imo.
Secondly, there's an implicit heteronormative assumption that AGM is where all 'gay content' should go, for containment. As only gay men could be interested in that and it's not relevant to straight men or could irritate, AGM is where it 'belongs'. But the point of AGM is to ask questions of any kind to gay men, as a demographic, for their views, not for it to be a silo for gay content. Gay or bi themed content can be asked anywhere on the site, just as straight-themed content can be. Calls for gay content to be banished to AGM come generally from some people who are just not comfortable rubbing up against 'gay' on equal (or any) terms.Sorry but that's their problem. But what's worse is that they don’t even recognise that because it's so inbuilt.
If the objection is that Etc is not for sexual content at all, okay, but I don’t see people saying that a thread like 'What is the hottest girl member' shouldn’t be here for that reason. There may be objections on other grounds but not because it's sexual in nature and not generally relevant to gay men. Why is that?