Lately Cthulhu brought deregulation of the financial sector, corporate personhood, reduced maximum tax rate and Investor State Dispute Settlement.

Of course neoliberalism that produces those policies and with lately drives much of Cthulhu's direction can be thought of as an extension of left liberalism of the 19th century but today's left doesn't like it. Of course the cathedral produces corporate personhood and the cathedral deregulated the financial sector but if that's what you call "progressivism" people that call themselves progressive aren't in favor of that.

they see said politics as conforming if unchecked to a vaguely Marxian notion of progress ever leftward

Today's left doesn't. It doesn't like that corporations gain more and more powerful as things progress. It's afraid of technology. Just look at GMO. Do you see today's left celebrating GMO's as valuable progress that moves society forward, the way the left did celebrate nuclear power in the 1950's and 1960's?

Of course the cathedral produces GMO's but if you label that position that supports GMO's as progressivism than people who self label as progressives don't really hold that position strongly.