To answer your question. No not at all, I typically go out of my way to say hello to everyone at the park regardless of skill level.
I know that there is a lot of nuance here - 4 years at the park, but how often? How old are you?
Like most people here have already said, I would reckon that after that long, and no interactions, maybe try to step outside of your comfort zone and at least give a few people you recognize a fist bump when you arrive or leave. Might seem weird at first, but that’s an easy, low social commitment interaction that can open up some conversations.