“Communism bad”
“Why?”
200 year old tropes so ancient they were debunked by Marx himself
Of course, you go through the motions of explaining the most basic political concepts that could be grasped by skimming the cliff notes for literally any Marxist works
“Friedrich Engels? Is he like the president of Germany or something?”
It’s like a kindergartener trying to teach you calculus.
Right! This is a criticism of philosophy in general, and I think it's very well-founded. In particular, the incentive structure of professional philosophy tends to encourage this kind of abstract theorizing that's disconnected from real-world social ills. Any kind of "applied" philosophy (applied ethics, applied political theory, philosophy of any particular science, &c.) is very much treated as a kind of second-class research project within the profession, and inferior to "pure" metaphysics & epistemology. My own area of specialization, foundations of climate science, is no exception here: making contact with concrete problems, or engaging with actual scientific work, is always seen as less prestigious than working on pure logic-chopping abstract theories.
I do think you're right that you're not incredibly likely to find "practicing" Marxists at the upper echelons of tenured R1 philosophy (though there are a few prominent exceptions that I'm aware of, and it still seems a bit more common than it is in most other disciplines). However, there's a vast underclass of (let's say) lumpenprofessoriat members–adjuncts, community college professors, non-tenured lecturers, and so on–that is, in my experience, extremely likely to endorse and be engaged with Marxist thought. As you say, this is almost certainly down to material conditions, at least to a great extent. I do think that a background in philosophical reasoning can help with  though.
Yeah it does seem to me that philosophy department's and the imposition of 'publish-or-perish' culture there (in a place where that makes possibly the least sense), compounds the issue of people starting their careers as academics and searching from a cottage-industry to milk for the sake of publishing; which is obviously not the kind of environment where philosophy will best do it's actual job of helping to dialectically clarify and conceptually develop the other areas of science, ethics, politics and aesthetics (in collaboration with these fields obvs). There are exceptions but they are still only exceptions which prove the rule imo.
Yeh the lumpen-intelligentsia has far more Marxists in it (as you can see on this site) than many or even most current demographics in many societies, which is interesting as they are now the large majority of actual workers in higher education and yet remain largely invisible.