Among many ideas for improving democracy, disenfranchisement is probably the one most often tried and history clearly shows that it's unmaintainable. Sooner or later it always gives in and nearly everyone gets to vote. In modern US it will be sooner.

There's simply no realistic path where people move into a large, modern European* country and remain second class residents with limited influence over the government. This state won't last a single generation.

* USA included by heritage if not by geography