@mrdiamondj I wish I shared your optimism.
I think it is far more likely that we will see closed leagues in Europe—the Super League—before we see promotion and relegation in MLS. If anyone does it first, it'll be NWSL.
Big soccer clubs all over the world are envious of how much money the NFL makes, despite only being popular in a handful of countries. They want to be like the NFL. Only way to do that is a closed shop.