Silly
However we are not in a life or death situation anymore so (at least many of us) can override any instinctive suspision of all things foreign i.e. a gay couple at high school aren't going to wipe out the straight kids thus they've been accepted.
It seems simplistic to me to suggest however that evolution acts to concentrate selfish genes - depending on the definition of selfish. Evolution can develop traits that are markedly unselfish, such as the poison in certain frogs - which might not aid an individual frog from being eaten but will protect the species as a whole.
I wonder also whether traits may develop which offer no advantage to the species but that also offer no distinct DISadvantage and thus may be allowed to progress. This could be a route through which any genetic susceptibility to homosexuality could travel (again I'm ignorant of where the scientific world stands on nature vs nurture as far as homosexuality goes)
The term selfish gene does not refer to genes for selfish individuals. It means that the genes themselves evolve in a way that promotes the "selfish" best interests of the genes. This is in opposition to the (erroneous) idea that evolution favors individual organisms that are most fit to survive, or that it favors communities that are most fit to survive. The genes are the "replicators", the things whose relative success drives evolution; organisms, and communities of organisms, are just vehicles for the genes. Our genes have "learned" that they can promote their own propagation by inducing the creation of these amazing tools — us. All the genes "care" about is that they, the genes, are propagated; sometimes that is is promoted by creating vehicles that survive well, sometimes by creating vehicles that are very fragile but very prolific, and sometimes it's in the best interests of the genes that individual organisms sacrifice themselves for others. What all these have in common is that they benefit the genes, regardless of the welfare of individual organisms. Hence the metaphorical use of the word "selfish".