I'd agree that not all 20th cen Philosophy is worth reading (there's a reason I didn't bring up Derrida or Lacan, for instance) but I find "meaningless word salad" accusations levied against the critical theory of the Frankfurt school and Habermas, and Foucault's work much harder to justify (I haven't read the sokal book in a while, but I don't think these thinkers were really a focus of the critique—it was more so the thought of derrida et al that followed on their heels). The Frankfurt school is sometimes a bit melodramatic and rhetorical, but their thought collectively actually does contain substantive argumentation and elaborates significant concepts that were important in establishing a critical reorientation in the new political and technological systems of the modern world, and, I think does what philosophy should: namely get us to question our own preconceptions, our social environments, and what kind of existence we should strive to achieve for self and other (in fact, Marcuse is one of the few philosophers to argue firmly for the positive beneficiary potential of technology—many of the more renowned philosophers on technology are usually far more pessimistic about its prospects, even stemming back to Socrates as rendered by Plato). The same goes for Foucault—his arguments and overall technique and program are worthy of respect, even if some of the people that adopt his ideas are overzealous and far less nuanced than he was (the debate between him and chomsky is great for instance, because they both have radically different approaches and perspectives but both get at some essential truths)

I'd say that the solidity of many of pg's theses stems from the fact that they aren't actually developed—to use this one as an example, it basically amounts to: "what should one do? make things that yield net good". That's great and all, but for this to have any real potency or meaning we'd have to elaborate what good actually means here, and it is in that analysis where actual philosophizing begins and where an empty platitude can become an actual thought worth sharing. Unfortunately, I don't think, as others seem to think, that pg is some deep thinker that is portraying deep insight "simply"—he is essentially just not a deep thinker at all. If you read any of his works with a critical eye you will note that he completely buys into the prevailing social and economic organization of the world, and that he is, in this sense, a fish who is quite happy to leave the water it swims in unexamined. He does not even really try to justify this acceptance—it is simply taken as a prior that this mode of organization must be acceptable (I assume because it made him rich and continues to make him money) and he feels no need to even justify it with any seriousness, acumen, or depth of research—at best he offers tautologies that rely on undefined terms (e.g. like we have here with "the good") for their "universal wisdom and truth". His writing is so narrowly focused on individualism that it fails to become critical. We are not isolated atoms operating in hermetically sealed tanks—any serious examination of how to live requires questioning whether or not the prevailing social conditions require modification. The only level of engagement pg has in this arena that I've seen is essentially to just try to convince people to found startups—what sparkling insight! It is this lack of critical perspective that makes much of his work worthless, in my view, yet he acts and presents his writing as though his philosophical learning is on the level of the ancients. He desperately wants to present and style himself as a learned man of letters without having actually seriously engaged with the literary tradition in any real sense (or at least he presents basically no evidence of this). Not to mention the downright harmful ideological crap he spews:

> The other reason I wouldn't want to define any thresholds is that we don't need them. The kind of people who make good new things don't need rules to keep them honest.

It's hard to read this as anything but a thinly veiled argument that people in the particular industry that makes him money should be subject to no oversight by default. He takes a jab at "the Victorians" for centering their lives around monotheism but then asks readers to take it on faith that the individuals that he might personally adjudge to be the makers of good things are de facto in the right and trustworthy. It's just laughably uncritical, uninteresting, and unscientific writing that basically always boils down to a cherry-picking argument from authority, N=1 style reasoning, egotism, and the myth of isolated "genius".