E6 expert here, I've said it before and I'll say it again:
Most furries aren't really 'in to' the porn. Most do not even participate in the furry community. The "furry community" deliberately ignores these people because the alternative is accepting something very uncomfortable.
I think there's a huge segment of furries who are either HMOFA Chuds or just quiet art enjoyers that are never counted in any survey or poll.
621's upload pages, if anything, seem to be 50/50 at least between straight and gay content. I'd wager the split is close to the same.