I'm inclined to agree that immigration right now is partially a short term tie over as we move to a more automated lifestyle where rationing and universal basic income will become necessities. I think 100 plus or so years from now the world is in a sense going to flip. I see lower birth rates, longer life spans, and no real retirement age. I picture robotic maids/housekeepers. Individuals not owning cars, but essentially having a driverless Uber-like network of highly efficient cars. Lot of time spent in Virtual Reality (simulated vacations etc). Tones of low value add jobs will become extinct and changed into care giver like jobs for the elderly.
I don't mean this as a negative vision, I think life in 100 years will be a LOT better than it is now. I think though that it will be unsettling for a lot of people to go through so much change.
Lol thankfully I’ll be long gone in 100 years