On a purely rhetorical point, it seems like the whole counterargument from Gwern is just an argument-by-disorganization or something to that effect. He doesn't actually challenge the factual information presented, but does shift how those facts are framed and what the actual contention is in the background, and then avoids actually engaging with the new contention from the bottom up.

In a lot of discussions with singularity cultists (both pros and antis) they assume that a true superintelligence would render the whole universe deterministically predictable to a sufficient degree to allow it to basically do magic. This is how the specifics of "how and why does the AI kill all humans again?' tend to be elided, for example. This same kind of thinking is also at the heart of their obsession with "superpredictors" who can, it is assumed, use some kind of trick to beat this kind of mathematical limit in certainty (this is the part where I say something about survivorship bias). In the context of that discussion, the fact that a relatively simple arrangement of components following relatively simple, deterministic rules is still not meaningfully predictable past a dozen or so sequential events due to the magnification of the inevitable error in our understanding of the initial circumstances is a logical knockout.

Rather than engage with this, however, Gwern and his compatriots in the thread focus in on the tangent about how high-level pinball players are able to control for that uncertainty by avoiding the region of the board where those error-magnifying parts are. However this is not the same argument and begs the question of whether those high-chaos areas are always avoidable as they are in a pinball machine. Rather than engage with that question, Gwern doubles down on the pinball analogy, shifting the question even further from "how well can we predict the deterministic motion of a ball given the inevitable uncertainty of our initial state" to "how many ways can we convince a third party we've gotten a high score on a pinball machine". At this point we're not just moving the goalposts, we've moved the entire stadium into low earth orbit and gotten real cute about whether we're playing 🏈 or ⚽ football.

And given the conversation surrounding the thread and these topics on LW I'm not even going to assume that such a wild shift is the result of bad faith instead of simple disorganization and sloppiness of rhetoric. This is what happens to a community that conflates "it makes me feel smart" with "it actually communicates the point effectively".