Earlier quoted context omitted.
We have something like that with "golden visas/golden passports" already here in Europe. The result was a bunch of Russian oligarchs with Schengen freedom of movement [1]. [1] https://www.dw.com/en/eu-threatens-legal-action-over-maltas-...
So maybe we don't want all the rich people? And we probably want some of the poor people. There is a shortage of all sorts of labor afterall. The real issue is that there is no good way to verify the identity or non-criminal nature of any of the migrants. You can create a solid ID at the time of entry and start tracking there at least.
Just as there was no good way for Diogenes to verify which bones belonged to Alexander's father.