For me recent means "less than 100 years", I am European.
Recent means not having a clear bloodline of several generations of ancestors (preferably a majority of them) who were part of the club.
Now for citizens whose bloodlines have been part of the fabric of society (the club) for 100+ years, exile should be very rare and require a high threshold of evil committed and so on.
But I mean once you are ostracized (and that is one of the first forms of democracy we have historical proof of, people voting with shells to decide whether to kick out a member from society, shell is ostrakon in Greek, hence ostracize), where you end up going is none of our business, we kick you out of the casino then if you have a place or not, we could care less.
The lives of non citizens cease to have any inherent values, their welfare stops being a concern of the nation.
Enslaving them as you proposed is a completly different affair that would violate basic constitutional provisions in many countries.
Now for the USA specifically iirc there are very clear SCOTUS decision about a constitutional impossibility of removing citizenship from people born there, so unless an amendment is passed, that's it.
While naturalized citizens can lose citizenship easily, it's just about congress passing laws determining when that can be the case and the executive enforcing them. Some such laws exist and courts have only discussed their application, the constitutionality of stripping naturalized citizens of citizenship afaik is not in question.
But the UK does strip citizenship from people born there regularly (220 case 2010 to 2022 according to this article), one such case got a lot of press coverage (UK born Bangladesh origin girl going to fight for Islamic terrorists out of the country)
https://www.bbc.co.uk/news/explainers-53428191
So as with any other topic about society rules, you have a constitution, then general laws, and you apply them, and there is nothing incompatible with liberal democracies about denaturalizing.