Afghanistan - economically not a big impact. The economic pressures in the 80s were low agricultural productivity requiring imports from Western countries, low oil/gas prices and productivity, endemic corruption. And if we really want to be pedantic, nobody forced USSR to invade Afghanistan.

I had to look up Jeffrey Sachs (0). He was an adviser-that is all he did. He did not impose anything on Yeltsin or Russia.

I agree that American decline will not resemble Russian collapse. Their commonality is both declines have internal causes. But other than that there isn’t much in common.

(0) https://en.wikipedia.org/wiki/Jeffrey_Sachs#Russia