"So while expansions in the wealth gap have become sport for the partisan and economically illiterate on both sides of the political divide..."

"... the real truth is that the sentient among us should cheer every time they read of rising inequality."

The sentient should cheer because it signals enterprise being rewarded, freedom to keep the fruits of one’s labor, and then for all of us not rich it signals that our lives are getting better and better; the lifestyle disparity between us and them (the rich) shrinking precisely because economic achievement is taking place.