The theory is that you both a) have relatives/other people that you care about that benefit from this, and b) that you will benefit from it when it's your turn to live even longer.
Of course, it's yet to be seen how well b) will play out in practice.
So you thrown bad money towards Ponzi scheme. Can I now stop throwing good money towards it?
Note that "we voted to confiscate your assets" is NOT a valid vote. "No taxation without representation" fails where we have no hope to recover what we've wasted here.
Or, as you seem to be suggesting, we're just waiting for a big crash while making sure it will be real big, while crunching in process.
Not if you're from my country, because it's the law for you to throw money to it.
But yes, it appears we're waiting for a big crash, which is likely the result of those who __are__ likely to profit from it represent a substantive portion of the electorate, resulting in our leaders being reluctant in finding other/better systems.
We already know that b) is not going to work in practice, because of the population curve. So, there's that. Why should you pay for something you will never get yourself?
How can we bootstrap anything with those payments, where they all go to the retired already? Can't spend same payments twice. And the balance isn't becoming better here.