Jail is the best place to be lategame. Don't have to pay someone rent if you can't move. And no risk of picking up a tax card.
It's not a punishment to sit in jail, it's a privilege, if I could. I'd spend the entire game in jail. It's the only place you're safe.
Get the fuck out. In monopoly it's called Jail. And Monopoly is the topic being discussed.
So no one cares about if it's called Prison or Jail in the real world. We're not talking about the real world. We're talking about Monopoly.