Not arguing cause I can definitely see both sides, but what's the point of calling it worlds if it's all US teams, I mean you might as well call it NCA 2.0
The two per country rule isn't fair in a lot of sports, but I can see why they have it in place. If international teams are like hey we won't make it past day one, what's the point of spending thousands and traveling thousands of miles for one day. Yes some would still do it for just the one time experience, but what's the draw for getting them to come back year after year. I also thinks its partially a money gaining deal for the people running worlds.
I also want to say that worlds > ICU simply because it gets more recognition and attention from every team that's attending. And I would think the international teams know this, they want to compete in front of a big crowd and have a big awards ceremony, rings, etc. And let's face it, audience wise people attend worlds more then the ICU competition. I would say there's a lot of aspects as to why they have the rule.