General remark: At some point I need to write a post about how I'm worried that there's an "unpacking fallacy" or "conjunction fallacy fallacy" practiced by people who have heard about the conjunction fallacy but don't realize how easy it is to take any event, including events which have already happened, and make it look very improbable by turning one pathway to it into a large series of conjunctions. E.g. I could produce a long list of things which allegedly have to happen for a moon landing to occur, some of which turned out to not be necessary but would look plausible if added to the list ante facto, with no disjunctive paths to the same destination, and thereby make it look impossible. Generally this manifests when somebody writes a list of alleged conjunctive necessities, and I look over the list and some of the items seem unnecessary (my model doesn't go through them at all), obvious disjunctive paths have been omitted, the person has assigned sub-50% probability to things that I see as mainline 90% probabilities, and conditional probabilities when you assume the theory was right about 1-N would be significantly higher for N+1. Most of all, if you imagine taking the negation of the assertion and unpacking it into a long list of conjunctive probabilities, it would look worse - there should be a name for the problem of showing that X has weak arguments but not considering that ~X has even weaker arguments. Or on a meta level, since it is very easy to make things look more conjunctive, we should perhaps not be prejudiced against things which somebody has helpfully unpacked for us into a big conjunction, when the core argument still seems pretty simple on some level.

When I look over this list, my reaction is that:

(1) is a mainline assumption with odds of 5:1 or 10:1 - of course future intergalactic civilization bottlenecks through the goals of a self-improving agency, how would you get to an intergalactic civilization without that happening? If this accounts for much of our disagreement then we're thinking about entirely different scenarios, and I'm not sure how to update from your beliefs about mostly scenario B to my beliefs about mostly scenario A. It makes more sense to call (1) into question if we're really asking about global vs. local, but then we get into the issue of whether global scenarios are mostly automatic losses anyway. If (1) is really about whether we should be taking into account a big chunk of survivable global scenarios then this goes back to a previous persistent disagreement.

(2) I don't see the relevance - why does a long time horizon vs. a short time horizon matter? 80 years would not make me relax and say that we had enough serial depth, though it would certainly be good news ceteris paribus, there's no obvious threshold to cross.

Listing (3) and (4) as separate items was what originally made my brain shout "unpacking fallacy!" There are several subproblems involved in FAI vs. UFAI, of which the two obvious top items are the entire system being conducive to goal stability through self-improvement which may require deducing global properties to which all subsystems must be conducive, and the goal loading problem. These both seem insight-heavy which will require serial time to solve. The key hypothesis is just that there are insight-heavy problems in FAI which don't parallelize well relative to the wide space of cobbled-together designs which might succeed for UFAI. Odds here are less extreme than for (1) but still in the range of 2:1-4:1. The combined 3-4 issue is the main weak point, but the case for "FAI would parallelize better than UFAI" is even weaker.

(5) makes no sense to ask as a conditionally independent question separate from (1); if (1) is true then the only astronomical effects of modern-day economic growth are whatever effects that growth has on AI work, and to determine if economic growth is qualitatively good or bad, we ask about the sign of the effect neglecting its magnitude. I suppose if the effect were trivial enough then we could just increase the planet's growth rate by 5% for sheer fun and giggles and it would have no effect on AI work, but this seems very unlikely; a wealthier planet will ceteris paribus have more AI researchers. Odds of 10:1 or better.

On net, this says that in my visualization the big question is just "Does UFAI parallelize better than FAI, or does FAI parallelize better than UFAI?" and we find that the case for the second clause is weaker than the first; or equivalently "Does UFAI inherently require serial time more than FAI requires serial time?" is weaker than "Does FAI inherently require serial time more than UFAI requires serial time?" This seems like a reasonable epistemic state to me.

The resulting shove at the balance of the sign of the effect of economic growth would have to be counterbalanced by some sort of stronger shove in the direction of modern-day economic growth having astronomical benefits. And the case for e.g. "More econ growth means friendlier international relations and so they endorse ideal Y which leads them to agree with me on policy Z" seems even more implausible when unpacked into a series of conjunctions. Lots of wealthy people and relatively friendly nations right now are not endorsing policy Z.

To summarize and simplify the whole idea, the notion is:

Right now my estimate of the sign of the astronomical effect of modern-day economic growth is dominated by a 2-node conjunction of, "Modern-day econ growth has a positive effect on resources into both FAI and UFAI" and "The case for FAI parallelizing better than UFAI is weaker than the converse case". For this to be not true requires mainly that somebody else demonstrate an effect or set of effects in the opposite direction which has better net properties after its own conjunctions are taken into account. The main weakness in the argument and lingering hope that econ growth is good, isn't that the original argument is very conjunctive, but rather it's that faster econ growth seems like it should have a bunch of nice effects on nice things and so the disjunction of other econ effects might conceivably swing the sign the other way. But it would be nice to have at least one plausible such good effect without dropping our standards so low that we could as easily list a dozen equally (im)plausible bad effects.

Even without doing any calculations, it is extraordinarily hard to imagine that the difference between "world at war" and "world at peace" is less than the difference between "world with slightly more parallelization in AI work" and "world with slightly less parallelization;"

With small enough values of 'slightly' obviously the former will have a greater effect, the question is the sign of that effect; also it's not obvious to me that moderately lower amounts of econ growth lead to world wars, and war seems qualitatively different in many respects from poverty. I also have to ask if you are possibly maybe being distracted by the travails of one planet as a terminal value, rather than considering that planet's instrumental role in future galaxies.