The percentage of service people who wouldn’t want to serve with out gays and lesbians is in any case a red herring. They serve with whom they are commanded – I think it’s called military discipline. I imagine that a fair number of American service personnel in the 1940s wouldn’t have liked the idea of serving alongside black soldiers, but President Truman did the right thing and de-segregated the military. Racism was defined as the source of indiscipline, not the presence of black people. The same principle applies to homophobia.
The US military can’t stop the straight guys from being sexually inappropriate with the female recruits, why the hell do they care about the gays?