I doubt Diddy is a Mets fan, in the Welcome To Atlanta remix video he was wearing a Yankees jacket and fitted.
NYC brehs regularly wear attire of teams they don't root for. I've seen brehs with Marlins fits in NYC before, even I thought about buying Charlotte Hornets graphic tees cause I like the colors even though I'm a Knicks fan!
I once met a dude from the BX who had a Yankees tat and he didn't even watch baseball
He got the tat to rep the BX rather than the baseball team.