There used to be writing that was "middlebrow." You'd find it in urbane and smart publications that were lower than academia and fine writing (highbrow) and higher than sports columnists and dimestore novels (lowbrow).
It was always a limited market. When Henry Fowler self-published his own set of essays, it didn't do well because, said his biographer G. G. Coulton, it was "neither good enough nor bad enough for popular success."
It has long been the case: If you want to make good money, you can't limit yourself to middlebrow pieces, hence H.L. Mencken, as co-editor of The Smart Set, siphoned off less satisfactory submissions into a magazine for "the morons." He made a killing:
Parisienne Monthly Magazine, a fifteen-cent pulp devoted to trashy short stories and novelettes set in France, became so successful that they launched two similar publications, Saucy Stories (in 1916) and Black Mask (in 1920). All were edited anonymously and with the utmost contempt--Mencken referred to them as "the louse magazines" . . . [They later] sold their interest in all three magazines for $60,000" (about $1,000,000 in 2023 dollars). Terry Teachout, The Skeptic: A Life of H.L. Mencken (2002), 122.
But what exactly is "middlebrow"?
Becca Rothfeld grapples a bit with the question in this essay, though I'm not sure she realizes it.
Her conclusion: Middlebrow is public discourse: a conversation between an intellectual and her audience.
She laments that the people who ought to be writing middlebrow pieces opt, instead, to talk down (lecture) to their readers. They pander to them, when they should, instead, be working with them to figure things out.
I'm not sure I fully agree with her pithy essay, but I like its angle.
Thought, she points out, isn't static and grasped. It's a journey, a thing to be worked out. Public intellectuals who spoon-feed their audience with cliches and ready-made formulas aren't thinking: they're proclaiming, like a first-grade school teacher solemnly enunciating how a "long A" sounds.
She doesn't like it, and she's correct. It's obnoxious and completely wrongheaded in its approach. Truth is found in dialogue, not monologue. Even when we think inside our heads, it's often in dialogue form.
It's just surprising that she's writing all that in The Yale Review. Within her criticism is a distrust of experts and officials who dictate and expect "the morons" to listen.
Immediately within her criticism is a distrust of COVID lockdowns, masks, and vaccines.
Deep within that criticism is a distrust of gnostic culture, whose presuppositions include the assumption that truth is static, graspable, and applicable to society as a whole, in a top-down approach wherein the smart set tells the morons what to do.
If the academic humanities too often address only siloed experts, then pop philosophy too often addresses an audience of imagined idiots.