You know, why are there gay Christians? Doesn't the Bible explicitly say they are not going to heaven.
At most it might say it's a sin, more or less, depending on translation and interpretation. One no worse than, say, drunkenness or revelry or extortion. Probably no more of a hindrance than being rich and definitely no more of one than being, say, uncharitable or whatev'. Lotta' shit's a sin, it doesn't stop sinners from being christian, plenty of denominations that hold it doesn't stop folks from receiving salvation, etc., etc. Doesn't seem to do much to slow down the sin, either, often enough, for that matter, and that still don't stop the sinners from calling themselves or being called christian.
There's a whole bunch of other theological guff that can get involved, but the short of it is it's only a meaningful barrier to being christian if the particular believer wants it to be, and roughly as important to the core messages and whatnot of the bible as whatever horseshit was invoked back when the churches were stanning for slavery. Bible says a lot of other shit a hell of a lot more important than its few lines that may or may not be explicit universal condemnations of homosexuality.
End of the day it's not the bloody bible (or the church, or churchgoers, or you) that decides if you're going to heaven, anyway, so far as christian metaphysics go. Feels like folks like to forget that a lot, some days.