It isn’t just aging whites, but aging people in general; basically, anyone eating up governemnt funds is viewed as an enemy by those that wish to use the same funds to buy votes with freebies.
When it comes to politics, voting, who the republicans are, who the racists are, who are the people on the wrong side of issues like global warming, and immigration, gay issues, God, etc, more and more they are identified as “old” white people, the dinosaurs, the people from the past who haven’t died off yet, the old bigoted America, the greying dying old school people with the twisted unhip middle American minds and beliefs,etc.
The left is farther isolating whites as old, and you may have noticed how they keep talking about the “uncle” that you have to defend liberalism, gay issues, gun issues, and on and on against at family events like Thanksgiving, that is another way of even separating younger whites form older whites.