I was talking with a guy on the weekend about things and he said for a gay man life is just beginning in your 30's, and after I thought about it I had to agree. For a straight man, once he settles down with a partner, it's not long until he stops being "a man" and turns into "a father" and from that point on (for the next 20+ years) his entire existence is about getting the newbie ready for the big, bad world. He stops living his own live and starts helping someone else live theirs.
Gay men don't have to worry about that. A gay man settles down with his partner, and then what? They get another dog? A cat? There life is still their own, and not someone else's. A gay man at 40 has more freedom than a gay man at 20, simply because the maturity has allowed them to grow. A straight man at 40 has a lot less, due to children.