It's not a calculation He ran at the time; He can, of course, recall that state of information and try to run it. More trade and prosperity means more people. So far, as people have become more prosperous, more of them have been Evil. This is confusing; you'd think that one of the things an agent would purchase with more prosperity is their preferred afterlife. Abadar's theories include that people prefer the Evil afterlives, that people prefer other things they can buy even though those things cause them to go to the Evil afterlives, or that people are failing to be coherent agents. It's probably the latter. it almost always is.

But at the time, that Keltham would make mortals richer wasn't obvious to Abadar; Abadar considered it a possibility, but expected most utility from Keltham to come from Keltham's understanding of coordination. If the reason that wealth makes mortals Eviller is related to their incompetence at coordination, then if they were more ideal agents they'd be less likely to go to the Evil afterlives, and Keltham would decrease the agents going to the Evil afterlives. Abadar's extrapolation from his own state of knowledge at the time suggests that He would have wrongly expected this effect to dominate the wealth effect He then considered unlikely.

Then there's the question of the resources transfer to Asmodeus; Asmodeus having more resources causes more people to go to Hell, drawing disproportionately but not wholly from the other Evil afterlives, and Abadar has some sense of the exchange rate. Inconveniently this number is within an order of magnitude of the expected effect from more coherent agents going to the Evil afterlives less. 

Then there's the question of whether Keltham at the time would predictably oppose people going to the Evil afterlives or the actions of their agents. That Abadar did calculate at the time; he quoted Asmodeus the evidence he'd observed over the prior that Keltham would oppose Asmodeus or Cheliax. Presumably Asmodeus attempted to price that in with respect to Hell, but not with respect to Abaddon or the Abyss. Keltham was at the Worldwound at the time, and most mortals at the Worldwound oppose the Abyss, though not usually through particular opposition to people going to the Abyss, which they mostly don't do as a product of the actions of Chaotic Evil agents with that aim in mind...Abadar thinks this factor will be smaller than the others and can be neglected. 

So time to return to the first calculations with more of His attention, as they're close enough to matter. Some chance of wealth causing more Evil, some higher chance of coherence causing less Evil, predictable expected Evil caused by Asmodeus....

Yes

He says when He's got an estimate He's reasonably confident in. 

It's not a calculation He ran at the time; He can, of course, recall that state of information and try to run it. More trade and prosperity means more people. So far, as people have become more prosperous, more of them have been Evil. This is confusing; you'd think that one of the things an agent would purchase with more prosperity is their preferred afterlife. Abadar's theories include that people prefer the Evil afterlives, that people prefer other things they can buy even though those things cause them to go to the Evil afterlives, or that people are failing to be coherent agents. It's probably the latter. it almost always is.

But at the time, that Keltham would make mortals richer wasn't obvious to Abadar; Abadar considered it a possibility, but expected most utility from Keltham to come from Keltham's understanding of coordination. If the reason that wealth makes mortals Eviller is related to their incompetence at coordination, then if they were more ideal agents they'd be less likely to go to the Evil afterlives, and Keltham would decrease the agents going to the Evil afterlives. Abadar's extrapolation from his own state of knowledge at the time suggests that He would have wrongly expected this effect to dominate the wealth effect He then considered unlikely.

Then there's the question of the resources transfer to Asmodeus; Asmodeus having more resources causes more people to go to Hell, drawing disproportionately but not wholly from the other Evil afterlives, and Abadar has some sense of the exchange rate. Inconveniently this number is within an order of magnitude of the expected effect from Abadar's early state of information from more coherent agents going to the Evil afterlives less. 

Then there's the question of whether Keltham at the time would predictably oppose people going to the Evil afterlives or the actions of their agents. That Abadar did calculate at the time; he quoted Asmodeus the evidence he'd observed over the prior that Keltham would oppose Asmodeus or Cheliax. Presumably Asmodeus attempted to price that in with respect to Hell, but not with respect to Abaddon or the Abyss. Keltham was at the Worldwound at the time, and most mortals at the Worldwound oppose the Abyss, though not usually through particular opposition to people going to the Abyss, which they mostly don't do as a product of the actions of Chaotic Evil agents with that aim in mind...Abadar thinks this factor will be smaller than the others and can be neglected. 

So time to return to the first calculations with more of His attention, as they're close enough to matter. Some chance of wealth causing more Evil, some higher chance of coherence causing less Evil, predictable expected Evil caused by Asmodeus....

Yes

He says when He's got an estimate He's reasonably confident in.