Nobody is going to pay for your pension forever. Do you really want to spend your entire life working?
What? I don't know where you are from,but in EU state pensions are absolutely paid until death.
In this scenario our society would be split into two groups if we pay pensions for eternity:
Those who lived long enough to receive their pension. Their body turns 30 again thanks to breakthroughs in science. And those who never age beyond 30 and so they never get their pension.
The first group effectively gets "basic income" and they probably own houses/apartments so their living costs are quite low. You can either let everyone have pensions or get rid of pensions.