> If you're friends with a lot of people who play games, and you learn games from each other, then it will be very rare to have a game that no one present has ever played before.

Only if you and all of your friends play from a very limited, range of games. In my experience, people like this exclusively play games that are currently or have been recently heavily marketed.

I'm friends with a lot of people who play games, I own a disturbing amount of games, and I sit at a table and play a game that no one at the table has played about weekly during normal times, maybe biweekly now that I'm stuck online. As a person who researches and finds a lot of games, it's very often me who's teaching the game that none of us have played.

In my experience, people who are really into games are constantly playing oddball, older, and obscure games, from the rules.