I never heard that idea until my teenage kids told me. I was in jr. high when the original was in theaters. I have no recollection of any gay themes.
They all laughed at my naivety. The song, volleyball game...everything went over my head. We thought their high five routine was awesome and copied it during basketball games. Thought we looked so cool.
My dad was in the Navy late 70s to early 2000s, had VHS tapes that guys had camcordered during deployments, especially to Desert Storm. One of the reasons I have fond memories of Top Gun is because it reminds me so much of my dad’s Navy. No gays, no women pretending that they’re fighting-men, no liberal BS. There was some “gay” humor, but only because everybody was straight or damn sure pretending to be straight, so it was just a funny way to make someone uncomfortable.