It's always abt the economy, otherwise why do people even bother to take in migrants with the backlash it produces?Economic stagnation is usually the excuse they give. Japan recovered from ww2 and two atom bombs without immigration.
They told us the Windrush generation was becouse we needed an economic boost through immigration but at the same time offering family's to emigrate to Australia for ten quid. It's never been about the economy.
Even tiny Singapore without much land takes in migrants but they do it cleverly - offering them work permits 1st and then only the cream of the crop is offered citizenship.
They do it to spur competition amongst their own citizens who they feel are pampered, gain more talents by enlarging that pool, have an adequate skill force to do manual work, etc.
Of course the Singaporean bottom feeders will feel the squeeze and if they don't level up despite all the opportunities given by their own society then they'll just fade away into obscurity.
But the smart man there will all be wringing their fingers in delight, thinking how they can profit from it.
Because, you see, humans are actually a resource.