This comic is... weird and bad in a lot of different ways at once.

Like, "everything is atoms" actually stood the test of time pretty well. Which makes it weird to trot it out as evidence that Wittgenstein was right and it's dumb to have beliefs about what's really ultimately real.

And "everything is mind or body" seems out of place here, since it's not monistic and it's not really pinpointing what was weird about Descartes' metaphysics. E.g., if you rephrase this claim as "everything is either spatially extended or not spatially extended", it sounds a lot less odd. Descartes' stumbles come from other quarters.

But the main howler here is "everything is noumena". You can rightly criticize Kant for being "too metaphysical" in some ways, but insofar as "noumena" means "everything outside our experience, which we mostly can't characterize or describe because we haven't experienced it", it seems very weird to single this concept out as a metaphysical excess. If anything it's more a sin of hyperskepticism, or of Kant's weird internally inconsistent Kant-specific methodology.