Don't try to reason with this population collapse nonsense. This has always been about racists fearing that "not enough" white westerners are being born, or about industrialists wanting infinite growth. For some prominent technocrats it's both.
The welfare state isnt predicated on a pyramid shape but the continued growth of the stock market and endless GDP growth certainly is.
>infinite growth, but growth is what is responsible for lifting large portions of the population out of poverty
It's overstated. The preconditions for GDP growth - namely lack of war and corruption are probably more responsible than the growth itself.
The welfare state is predicated on a pyramid-shaped population.
Also: people deride infinite growth, but growth is what is responsible for lifting large portions of the population out of poverty. If global markets were repriced tomorrow to expect no future growth, economies would collapse.
There may be a way to accept low or no growth without economic collapse, but if there is no one has figured it out yet. That's nothing to be cavalier about.