This is an election for our future, not an AARP meeting. You think the younger voters are going to scramble for Social Security protection like silver foxes scrambling for baguettes to stuff in their purses at a Boca Raton buffet?
The issues that the New Democrats are passionate about are issues that will help everybody, not just themselves--Medicare for all, protection of the environment, support for working families. As Bernie's slogan says, "Not me--US." So far, it looks like that message is working across demographics.
I love this video from 2016--still applies in 2020: