Because Trek sucks at romance so the viewers need to invent some?
I don't think O'Brien was at all gay. I think he was an old school male, a Sam Gamgee type of character who was more comfortable with males to socialize with and for whom women were more inaccessible. The sort of male you find in everything from Tolkien to Thomas the Tank Engine, written by males whose formative years were spent in all male boarding schools and who went on to work in all male environments. He's quite atavistic as far as Starfleet goes.
Really does remind me of Sam Gamgee and Frodo, O'Brien and Bashir. Bashir is much more the pretty boy (as is Frodo) and I think he could be read as sexually ambiguous.
