Also, more economists are suggesting that the economy is something of a pyramid scheme which requires ever newer, younger, bigger populations to increase demand. As people age, they buy less. Stocks will go down. Real estate will also. So if old age pensions go away, even the pragmatic folks who plan ahead will have little to invest in.
So the welfare states will change how they do welfare.
You say this stuff like people and economies cannot adapt. They will adapt. Some may do better than others.