Being a Pokémon fan is weird because it’s not like other fandom’s where you see someone who likes the same thing so you’re excited. Being a fan of Pokémon is like being a fan of sports but not a specific sport, just sports in general. It’s such a big franchise that it’s vague to what degree someone you see is a fan.
They could be fans of the mainline games, TCG, only like mystery dungeon, only be into the competitive scene, or just be a scalper, or maybe they haven’t played a game since generation two and they don’t know any of the new ones, but they’re still under the umbrella of Pokémon fan. But it doesn’t mean you want to talk to them because they had a mimikyu shirt on. It’s more like “yeah of course there’s a Pokémon fan here.”