@lain @PoalackJokes88 @Waldbrand Isn't that another level than our issue though?
I think PJ and I are probably closer in opinion on what to filter for than you and I, and we would both say that filtering for race is what we want. What we would be debating is how to do that in Ancapistan.

If you don't have the Mr. Lee’s Greater Aryan Urheimat Hong Kong passport, you can't come in or do business here, is, I would say, also trivially enforceable.

So in short, the disagreement wasn't about the governance in practice, by what measure to disallow people, just about feasibility of doing it with either a state or a voluntary company like in Ancap.
And from where I'm standing, both your proposal and a simple ethnic filter can be implemented in both systems