I’m not sure that pulp was quite “inherently racist.” You can’t get much pulpier than The Avenger, but Richard Benson’s cast of allies included a black couple, both college-educated and quite capable in a fight. I’ll certainly grant “frequently racist.”
But the pulp formula can be used just as well for narratives about black or East Asian or South Asian characters. (Which of course is a point your comment about Tonga makes.)
For that matter, Kipling’s story “The Men Who Would Be King” has a lot of elements reminiscent of Ruritanian fiction, right up until everything goes horribly wrong for the European adventurers (another way to reverse the formula).
Back when I was getting started on my series of campaigns recruited by prospectus, I ran a Champions campaign about masked adventurers in the San Francisco Bay area ca. 1920. One of the five heroes, Anubis, was black and used an ancient Egyptian motif in his costume. (I remember the players talking about the idea of his having a niece who took up the mantle somewhat later on using the nom de guerre of Ma’at.) We had one storyline about blockbusting in an Oakland neighborhood. Of course all the PCs, played in the 1990s, were on the side of equal rights, or at least willing to support their allies on it, which was a bit revisionist. But the formula could survive revision. (And you know, a white person who went outside the law to fight against racism in the 1920s might have at least as good reason to adopt a secret identity as a Klansman would.)
Confession time: I’ve never enjoyed listening to podcasts, so I hadn’t been paying much attention to these topics. (It’s good that I eventually did, however, as you will see that I was about to launch into a lengthy exploration of the picaresque in a different topic.)
The clash of ideas in picaresque fiction is implicit, in the successes of the lower class protagonist versus a parade of upper class marks, and in the episodic format wherein the protagonist moves from adventure to adventure without changing or growing as a character. In a sense, picaresque stories are anti-romances. I wouldn’t call them anatomies, except in as much as satire is an analysis and deconstruction of the thing it satirizes (in this case, society in general and upper class society in particular).
A late thought on this: a benefit of Ruritania is that you can’t run to the authorities, since they’re probably in the pocket of the Evil Duke and in any case unable to help you.