Setting aside the sad man that is Peterson, this rhetoric has always existed in some form throughout history as a way to shut down criticism.

Whether through 'whatabout-ism' (which points out issues on the side of the criticizer in order to assert their lack of ground to criticize), or through claims of lack of experience or knowledge (which must be 'made up for' to whatever extent the dismiss-er feels is warranted before they will accept criticism, which is probably never), this rhetorical device is just a trick to discount and dismiss.

The CurrentAffairs author seems to be taking this claim at face value, insomuch as they spend much more time attempting to validate Marx, rather than discussing the bad-faith employment of this argumentation.

Instead of devoting a whole article to attempting to somehow disprove the relevance of literal cleanliness to political acumen or the 'right' to speak on politics, it might have been better spent examining the purpose of these types of claims, or the mechanisms by which they function. There is one line- the literal last line of the article- in which "ad hominem" is said; it should not take that long, or require that much prefatory work, to name "I (selectively) don't listen to you because your room/body/desk/life is dirty" as such.