again and again the result was "because I had a friend who used to tell me about that kind of thing back then."

Be more social at the things you like and you'll make more friends who will also tell you about that kind of thing. 500 approaches, 100 replies, 20 aquaintances, 5 friends, 1-2 people who will tell you of dozens of that kind of thing. Also, host that kind of thing (after-parties, group rides, theater rental, etc.) with the $200.

Remember you didn't know all the things you like now in the past. This suggests you don't now know things you will like later. So try new things, some of which you will like.