But in any case, I think it's not that different as wanting a wife and kids. You need to be able to seduce someone, whether it's for a casual relationship, or for marriage. It's start with physical attraction either way. I don't think mentioning "I want to get married and have kids" will give you a free pass which is ironic considering many women complain men only want casual relationships.
Modern dating where people meet online makes it harder too. A gay friend of mine who is 60 years old says that back in the day, he would meet guys in saunas or bars, and older guy would have a chance. But online, nobody want to meet a 60 years old guy.