I used to go on the city bus and get like 20 people with street pass. For about 5 years or more it was really fun.
I live in a super tiny town on the edge of nowhere, so I only met like six people, who all regularly streetpassed with each other. So I set my router up with fakepass or whatever it was called, the software that let me streetpass with people all over the world, and that was huge fun. Then they set up some kind of thing where every Mcdonalds in NA was streetpass linked or something, so I didn’t have to do the router thing anymore, and I started making regular trips to the park beside McDonalds, because their wifi just barely reached and I’d get streetpasses.
I bought the Plaza DLC, whatever it was called, and I played every game for hours. It was just so fun to see that there were other people doing the same thing as me. It made everything feel a bit like an MMO. I wish it’d come back for the Switch 2.