Indeed, Jordan Peterson assertion about current strain of "postmodern neo-marxism (or neo-marxist postmodernism)" looks absurd taken at its face value, in a most superficial way.
But what this article suggests is that postmodernism is an actual "next" stepping stone allowing neo-marxist people to into full revisionist, neo-Leninist mode by getting rid of a practice as a necessary step to prove or disprove the neo-Marxist theory, or rather to reinterpret practice as such.
Leninism revised Marxism in such a way that the most advanced capitalist stage of the economical development was no longer a necessary prerequisite for the proletarian revolution. Any opportunity to revolt and overthrow the government weak enough to be overthrown will do for a Bolshevik, providing the ultimate purpose is to apply the marxist theory to the proletarian state development afterwards, in order to arrive to a practical vision of communism. Postmodernist neo-Leninists do similar mental trick, by taking out the requirement of practical application as an ultimate proof of any theory, including most importantly Marxist theory itself.
Within postmodernist paradigm practice as not a way to prove or disprove validity of the theory by comparing the verifiable outcomes of its application to the previous state of affairs or to the alternatives.
Practice is but a collection of perceptual phenomena (philosophical phenomenalism one of the sources of postmodernism), personified state-of-being-in-time-and-place.
Phenomena is behind the door, perception is a master key.
As soon as one may get rid of objective economic measurements of success or lack thereof of the Communist or any more or less diluted Socialist doctrine, there are endless possibilities to further the doctrine by comparing other things - i.e. subjective happiness of masses of the people under socialist regimes vs so-called capitalist regimes (I prefer more accurate label "free enterprise"). Which may be actually higher as socialist regimes present a singular narrative of "lucky us" vs "oppressed them" and by carefully controlling the ideological narrative in their mass media and polls, persist in presenting consistently better mass feelings, even if they are not supported in any way by economic prosperity of the nation.
Stalinism went to extraordinary lengths to falsify the objective economical figures, i.e. the collected harvest or the cars produced or the income of the individual family. It was hard job for the state statisticians to project an image of Soviet prosperity. It was easily disproved by applying correct science. The neo-marxist postmodernist offers a solution: lets concentrate on emotions, feelings, ranging from outrage to elation, lets read the individual twitter narratives instead of boring books. Lets talk about people having the most exquisite orgasm when doing nothing of value nor producing kids, but marching the mass demonstration or expressing themselves on stage.
Lets also get rid of historical and scientific research as such; instead present the steady narrative of linear progress. Today is better than yesterday, tomorrow is even better, and you are the best; we are all extremely proud of you. Target the being-in-time in the most direct way, go strait for the brain pleasure centers.
The removal of the most crucial aspects of objective reality from the narrative and replacement them with individual feelings (individual yes, yet measured via mass polls and noises of exaltation at mass performances) presents a wonderful opportunity for the new breed of neo-Marxist postmodernists: instead of controlling the economy for efficiency and desired material outcomes, one may simply concentrate on controlling mass feelings. Which are indeed, much easier to manipulate and fudge to achieve something resembling "happiness" or even "excitement about the future" on a mass scale, than to create a functioning, stable and sustainable economy to be proud of. Economy under such a revisionist neo-Leninst postmodernist regime is not about producing certain material output, but primarily a stage play, producing certain hormonal outpour among the mass audience.
Greed is good - says the caricatured capitalist, because greed stimulates the production and growth of wealth. But wealth is only my wealth, not yours, alas, poor Yorick.
Greed is good - says the postmodernist neo-Leninst, because it allows me attack the rich. Not to kill the rich and give to the poor, but to stage a mass spectacle about robbing the rich and giving to the poor and saving the damsel along the way. Watching such a happy western makes the audience feel better. Especially women.
Guy Debord wrote about Society of the Spectacle as he was frightened by Soviet staged trials against the enemies-of-the state, when the morbid story behind them became public in the West. And he watched the rise of the similar tendencies around him in Europe with alarm and indignation, compensating it with wit and mental brilliance of a desperate alcoholic.
Why to be alarmed - says the neo-Leninist postmodernist. Learn and use the technique, being as sober and vegetarian as some more efficient dictators in our history.