Which is where, exactly, for the people in question? i.e. what is the legal home country for most Roma in Denmark? Given folks like DHH have such strong opinions about this, I would expect they should be able to detail the specifics of the mass deportation plan they're proposing!
Presumably, if they are immigrants, then they have a passport and a legal home country. I agree with you that mass deportation (i.e. deportation of a whole group not based on individual guilt or innocence) is bad. Just saying that this particular argument isn't relevant.
Pardon my skepticism, but cursory web searching and LLM prompting is giving me responses like "a significant portion of the European Roma population faces high rates of statelessness or lacks basic civil documents", while citing real website articles with titles such as "Many Roma in Europe are stateless and live outside social protection".
That aligns 100% with things I've read previously, but that said, I'm not terribly well-informed on the topic and maybe I'm entirely wrong here. Do you have any links/info that support what you're saying?
Being literally stateless is not the same as not having a passport. (My father-in-law doesn't have one, but he's a perfectly respectable citizen!) Being in a foreign country without a passport is also not being stateless - it may well correspond to being an illegal immigrant, however.
It is quite hard to be made stateless. You have to be born in a very unlucky place.
All of this means that immigrants can be deported to their country of origin.
The articles I read yesterday indicated that it would be quite difficult to determine country of origin in many cases, due to complete lack of official identity documentation.