Now let's say in a few years, that inflection point happens where crypto sees an exponential rate of adoption. Every other country begins to use it, some ban it, many others adopt it. At that point, if not using crypto will put the US at a disadvantage, they have no other choice but to adopt it as well.

A semi-related example is the way many companies "disrupt" the markets e.g. Uber/Airbnb wasn't a threat to many cities, until it was. At which point, the demand for Uber/Airbnb outweighed the government's ability to do anything about it.

It's not the best example since some cities have done things about it and Uber/Airbnb, being a company, is easier to target.

With crypto, its decentralized nature makes it much more difficult to control and attempting to ban it will raise issues around free speech.

That's not to say countries won't try and succeed in getting it banned, though in the case of the US, I don't think it's as cut and dry.