I think it more "a person capable of empathising with the users". Knowing the internals of how the baseball industry operates isn't relevent here. The relevent experience is being familiar with how the viewers interact with baseball.
Having said that, it seems like this applies mostly to frontend people writing the consumer facing portions. There are plenty of jobs where your users are other people in the company, or partner companies. In those cases, understanding the bussiness tends to be far more important than understanding the user experience.
For parking garages, the relevent experience would be someone has used them a lot. Or at least someone who is familiar with driving a car.
Having said that, it seems like this applies mostly to frontend people writing the consumer facing portions. There are plenty of jobs where your users are other people in the company, or partner companies. In those cases, understanding the bussiness tends to be far more important than understanding the user experience.
For parking garages, the relevent experience would be someone has used them a lot. Or at least someone who is familiar with driving a car.