Immigration won’t solve the problem forever. Eventually every country is going to be putting in measures to hold on to their own citizens. There’s also an ethical question about accelerating depopulation in other countries by “stealing” their citizens.
And this does not solve the problem of overall global decline. unless we’re going to “close down” some countries and redistribute all the people. Even if we did that, Once the world population starts to fall, how are we ever going to get it back to replacement rate? In the longer term humanity will shrink and disappear, with increasingly hard and isolated lives for the survivors. I happen to think that the human race is a valuable and interesting part if planet Earth and we need to think about how we will protect it!
In the shorter term, Our entire economic and social structure is based on a growing population. It is going to have to adapt.
Just take housing, as one example. In Japan, there are right now many empty houses, indeed whole abandoned villages. This means house prices go down. In Italy they are selling houses for 1 euro. Great if you want to get on the property ladder, but what happens to those communities? What happens to the shops and cinemas and services now that there’s no one to staff them? And now we’re no longer building new houses. What happens to the construction industry? And how much of your pension is invested in housing or construction? What happens to people who bought their houses before prices collapsed? And that’s just one industry. Imagine this repeated across all industries and the kind of economic and social devastation that will result.
A falling population is the future. This is going to happen and we probably can’t stop it. We need to be planning now for how we’re going to adapt.