Now this is how you overthink Afghanistan. Robert Haddick summarizes at SWJ:
But was the Soviet strategy, which Goodson and Johnson blame the U.S. for following, really a failure? In “Follow the Bear,” an essay published in February 2010 by Proceedings, four field-grade U.S. officers (three of whom served in Afghanistan) claim that the Soviets improved their tactics around 1986 and by the end were implementing many practices now found in FM 3-24. The authors assert that the Soviet end-game exceeded expectations, that the Soviets departed Afghanistan on their own terms, and that they left behind a friendly government that had the potential to last – and did in fact outlast the Soviet Union itself (I have cited “Follow the Bear” elsewhere). They conclude that “following the Bear” is a good idea.
Not a single one of the Soviets' objectives in Afghanistan succeeded. (That's how you know if the effort failed!) There was no durable satellite regime installed in Kabul at acceptable cost, which is to say without a bloody, expensive and troop-intensive occupation. I haven't read the piece, but if Haddick's summary is accurate, what these field-grades are really demonstrating is that the Soviets mitigated the consequences of their Afghan blunder. That's not nothing! But it's also not success.
Sovietologists can correct me, but I don't think it's controversial to assert that the grinding war in Afghanistan contributed to the economic overstretch and popular disillusionment that tore apart the Soviet Union. To look at it from our perspective, if Hamid Karzai gets ousted and his government collapses four years after a U.S. withdrawal and the U.S. has ceased to exist, then yeah, we'd properly look up from the piles of burning tires around us as we scavenge for food along lawless highways leading to ever-more-apocalyptic landscapes and think, "Hmm, that wasn't such a success."