I have very little sympathy towards the Soviet empire, but the war remained on the Afghan side of the border, and was of a limited scope for most of its duration; construing the Soviet defeat into a direct cause of regime collapse is an extraordinary claim warranting extraordinary proof.
For example, one wouldn't claim that the de-facto American loss of the wars in Iraq and Afghanistan is directly affecting the stability of the American regime, would they?
Coming back to the Soviets, I would concur to a claim that the Afghan War was a failed national project, alongside the Chernobyl tragedy and the ecological disaster of the Aral Sea. The narrative I think proper here is first and foremost is the ordinary Soviet citizen's loss of trust in the Soviet way as such, rather than the specific fear of a foreign invasion.
For example, one wouldn't claim that the de-facto American loss of the wars in Iraq and Afghanistan is directly affecting the stability of the American regime, would they?
Coming back to the Soviets, I would concur to a claim that the Afghan War was a failed national project, alongside the Chernobyl tragedy and the ecological disaster of the Aral Sea. The narrative I think proper here is first and foremost is the ordinary Soviet citizen's loss of trust in the Soviet way as such, rather than the specific fear of a foreign invasion.