I love McGurl's work and enjoyed this essay from Bennett. However, I feel compelled to say you might be surprised if you ever visited Iowa City (lol) and talked to recent grads, profs, and students.
Despite the experience of walking into Prairie Lights and looking at the tables of bestsellers in the front... the millennial/zillennial/zoomer set of the last 10-15 years seem intensely aware of the school's history, and the larger historicization of the workshop model and of academic creative writing in the States.
In fact, in my experience a healthy % of students admitted into the 'major' MFA programs nowadays tend to write in some sort of avant-garde tradition. You'll find their names with equal measure in rags like Protean, The Baffler, n+1, Jacket2, Fence, and endless smaller leftist zines etc. etc. as you would the traditional outlets.
Further, and not to necessarily 'defend' Iowa, but you can find plenty of famous grads who wrote/write against its prevailing aesthetic. Here's a small and random grab-bag of great writers across the decades: alice notley, joshua clover, james tate, cathy park hong, john edgar wideman, michael lally, joyelle mcsweeney...