On the positive side the Taliban generally lack the technical skills and spare parts supply to maintain any of that equipment more sophisticated than trucks and small arms.

Maintenance for modern military gear can be quite expensive and challenging. My armchair analysis thinks that it’s more likely this gear would be sold to other interested countries if it was captured.

Like the Russians?

I suspect the kit will get bombed to smithereens by US et al too.

Modern armies do it to their own hardware if it’s at risk of being captured by the enemy. I guess there are few secretive things the Afghans got, but even that isn’t for wider consumption.

That demonstrably did not happen. Did you see the picture on the cover of all of the major news sites of the Taliban sitting in the presidential palace? At least according to Reddit (I'm not an expert on military weaponry) those rifles are American made M4s and M16s.