“Americans give, on average, about 10 times more of their income to charity than Joe Biden does. Voters can interpret that fact however they see fit.”
Brooks' next-to-last book was titled, "Who Really Cares, The Surprising Truth About Compassionate Conservatism." One of his surprising findings included the fact that conservatives were much more charitable -- even when it came to donating to secular charities, such as the Humane Society, etc. Presumably, the reason is the liberal world view which puts the onus on government for taxing citizens to use for helping the poor (as a substitute for voluntary charity).
When you look at Biden's charitable donations (or lack thereof), this theory really rings true.