A lot of discussion of immigration is framed around the distinction between movers and stayers. Until recently, most of what I’ve seen has framed “stayers” as those who see their economic interests as being threatened by competition from immigrants. To protect themselves, they want to restrict immigration, even if the consequence is to restrict the opportunities for “movers” from their own country. The harm to these “movers-out” is just collateral damage
But lately I’ve been seeing a different account, in which it’s the departure of the movers-out that is causing problems by reducing the supply of workers to provide services to, and pay taxes to support, the stayers (particularly, the old). In economic terms, the obvious solution would be to replace the movers-out with movers-in, but they are of the wrong religion, skin colour and so on, and are therefore rejected. That exacerbates visible economic decline, particularly in terms of the level of economic activity, even when income per person holds up or is sustained by transfer payments. This in turn produces support for Trumpism and its variants.
This story comes up most clearly in relation to Eastern Europe (most notably Hungary) following accession to the EU, but I think it’s applicable to many rural areas in richer countries.
The feelings of the stayers in this story are understandable. They liked things better as they were, and resent changes. But they are hard to defend in moral terms, since keeping things as they were requires massively constraining the rights of others to work, marry and live in the way they wish to.
On this account, there’s also a lot of self-selection going on here. Staying, and demanding that others do so, is a conservative and authoritarian choice, so the stayers will tend to be those in a given population who fit this description. This comes back to the question of why rural voters support conservative parties, even when those parties serve the interests of the urban rich. I’ve seen (but can’t now find) a very old discussion of this point in relation to France, where it’s been relevant ever since 1789. In the US context, it’s being rediscovered right now.