There's one very specific subset of heterosexual-supremacists that I do tend to suspect may be closeted and self-loathing; the type that present heterosexuality as a noble sacrifice in which people refrain from engaging in same-sex relationships (which are obviously more satisfying) out of an altruistic desire to perpetuate the species and maintain social order. Because none of the actual heterosexuals I know experience their orientation as a sacrifice. And OSC is probably the most blatant user of the "noble sacrifice" explanation.