Yeah, it’s just a song about young men hanging out with all the boys and having fun doing whatever they feel.
So you can interpret it to not be gay if you want… it is open ended when it says “do whatever you feel” so if you don’t feel like having gay sex then you can substitute whatever you want in there instead of gay sex. So it’s technically not about having gay sex at the YMCA. Technically.
Bottom line is if you think the song is catchy and like doing the fun dance routine, you don’t have to feel like it makes you gay if you do the dance. Just do whatever you feel, it’s fun!