Edit: this is out of date, see https://forum.effectivealtruism.org/posts/YuFD4v7DFBcM57eSA/consequences-of-animal-product-consumption-combined-model
The "meat eater problem" is the problem that, the more we enrich people, the more meat they will eat - which increases animal suffering.
Well I took my old analysis here, that was estimating the magnitude of the meat eater problem. Then I decided to combine it with the animal suffering numbers from my more recent estimate of the net farm animal suffering caused by farming.
In the process I found that my meat eater calculation included a critical misreading of York & Gossard. Fish consumption does increase as African countries get wealthier, by an estimated 0.79kg annually per $1000 GDP.
I'll suppose that 0.6kg out of this marginal increase is from farming. I'll suppose that 0.4kg of this is like catfish (because the similarly small tilapia is commonly farmed in Africa and other poor regions) and 0.2kg is like salmon.
Plugging these numbers into the animal welfare spreadsheet as a "diet" (too simple an action to merit uploading - it's just the kg quantities from the meat eater sheet, plus 0.4k for catfish and 0.2kg for salmon) I get -720 welfare day-points for the year's marginal meat consumption. This means that a $1,000 increase in GDP per capita for a person in Africa has an animal cost that is equivalent to -2 points on a -100 to +100 scale, which is 4% of the average welfare difference between living in India and living in Canada, using my sentience weights. Things may be worse in India/Bangladesh: presumably they fall somewhere between the average relationship for Asia (2.31kg) and the relationship for the West, Africa and the Middle East (0.79kg). The authors suggest that cultural factors drive the difference.
I'm ignoring the climate change costs of meat consumption because that can and should be left as part of the more general question of the link between economic development and long run GHG emissions. In any case, GHG emissions only make a relatively small difference on any short or medium run outlook, as I argued when I posted the farming analysis.
Given these assumptions about animal farming (which point heavily towards animal charity in the first place, anyway - see Shulman's comment in the original meat eater problem thread) I think these numbers suggest general agnosticism about the direct impacts of economic growth aside from the question of wild animal suffering. I would make an exception for pulling people out of serious poverty because the wealth-welfare relationship is solidly logarithmic. Per Footnote 7, York & Gossard seem to think that neither a linear model (which they present, because it's simpler) nor a logarithmic model (which they claim to have done) is decisively a better fit for the relationship between wealth and animal consumption.
I just had a very quick look-through of Y&G, but it looks like they tested for curvilinear (i.e., a log transformation of GDP) only. I could be missing a footnote, but I don't believe they included a second-order GDP term to test a polynomial relationship.
However, the findings of the 2013 paper largely support that, from my quick reading. The estimation of the second-order coefficient is significant but basically zero for most of the different data slices. Further, when they back out the inflection points, the income levels for the turning point of meat consumption are much higher than the turning points for other Kuznets curves ($45K relative to $3K-$12K in the general environmental KC literature).
But actually now that I'm digging in to the results, I think the tables report different numbers from the text. Neither Y&G nor RC&M are forthcoming about their units, which is frustrating, but at least Y&G discuss their results clearly. I'm a bit frustrated about the write up of this paper. I believe that you're reading the results correctly, unless the authors are actually using per capita GDP in thousands like Y&G and failing to report that (although that result wouldn't make any more sense). It does seem a lot higher than Y&G.
I'm losing faith in this paper now (at least in the result discussion), but I would like to check out the literature further and see if there are any other newer papers that can provide insight into the differences.