They (as a concept) may or may not be gay depending on the circumstances.
The entire point of a trap is to convincingly present themselves as the opposite sex until it is revealed what set of genetilia they have. For the person being the trap, it's 100% gay. But for the person on the receiving end,
>If you're into the trap and don't know that the person is a trap until the trap is sprung, and are instantly turned off or revolted,
You are not gay, because for what you knew the trap was the opposite sex until it was found out otherwise, and you still have no intentions of changing hetero sexuality.
>If you're into the trap and don't know that the person is a trap until the trap is sprung, but are into it anyway,
You're most definitely gay, if possibly only for girly guys / manly women. no two ways about it, though the whole trap facade is rather redundant.