Houkou does not prevent a Chinese citizen from leaving a town. People move around all the time. Houkou is about registering to receive public services in the new city within China.

In any case Houkou doesn’t prevent a person from leaving the country. A passport does, but this is the same in all countries.

> You see, it was always illegal to go outside of the country without Xi's approval and those approvals have mostly stopped coming.

There are hundreds of millions of trips out of China every year. A good number of them to the US for work. That fact is hard to square with what you’re saying.