Yes, that's right. Like I said, it was asked for and returned in kind to make a point.
It's a phrase that David Rubin uses to contrast with the term "progressive" left, which latter to some extent he still considers himself to be. According to him, the regressive left is doing all it can to regress people into infantilism; it doesn't actually give a toss about people, having completely lost its sense of fair play. It won't even listen, and seeks to protect itself by refusing to
discuss serious issues, instead resorting to name-calling and shouting -- even violence. It'll label anyone, even members of minority groups such as blacks, when it suits its agenda. The reason Trump was elected, even though people in general thought he wasn't qualified to be president, was because people wanted change; wanted to escape from the deadening hand of political correctness. The regressive left still hasn't accepted this and is doubling down on its message.
Watch Ken Wilber speak about this at around 2h 31m 10s here:
As for me, I'm neither left nor right. The nearest term I'd sort of accept is libertarian, which the progressive left used to be. Libertarians can be found both on the left (now quite rarely) and the right.