If you want someone to say "you should have lost your virginity by age blah blah" or "you should have your own house by blah blah" zero chance I would do this, because I have no clue what anyone else's life has been like.
I don't even know if someone else has the value of "must achieve milestones", so how could I tell them they must have done something.
I think one very annoying type of milestone is if a person is well-traveled. Today that means traveling to France, Italy, Spain and taking thousands of pictures of yourself with your dopey self-important friends and snapping pics of food they are about to eat and iconic locations, and then uploading it to Facebook or Instagram to make people jealous. I have no desire to travel, but i have been to 800 or 900 pro sports games in New York City area.
Guys who have been with a lot of women, there is a part of me that is still jealous of that and makes me feel like i missed out. I have been with some gorgeous women but it was a long time ago and i have basically thrown in the towel. Guys who are players have a kinda cut-off disconnected vibe to them, as if they just have sex like robots and then go back home and charge an AC adapter by plugging it into their backs, just not very human or real people. I don't think people in general should have sex until around the age of 18 or so, male or female, but not like anyone today will follow that advice. I think as a guy, showing pictures of women you have been with is very creepy, or to say, i was with X amount of women, very tacky.
I think mentioning what kind of car you drive or house you own or luxuries would only serve the purpose of bragging at parties or when dealing with materialistic women you are trying to impress. It is easy to own a home, because it all depends on the location. I don't think men care to own homes generally with a manicured lawn and all that, unless it attracts a woman. Guys would be happy to live in a hut using lanterns or candle-light and without electricity, if not for the possibility of attracting a woman.