The literacy rate in Tsarist Russia was ~50% in 1916. The Soviet Union managed to raise it to 75% in two decades, despite a largely rural population, near-zero infrastructure, going through a civil war, famine, gross government mismanagement, being flat-broke, and having incredibly incompetent, and ideologically-bound leadership, that was more concerned with waging a war against its people, than actually governing them.
If you're telling me that the United States, with an unlimited budget couldn't accomplish the same in two decades of occupying Afghanistan, I'll tell you it's not because it couldn't do it. It's because it didn't try.
> No form of social engineering would solve this
No form of social engineering if you don't actually try to build a national identity is going to solve that. National identities don't arise by an act of God, they arise out of focused top-down propaganda and education and cultural efforts. Every country that has a national identity built one through such a manner. Afghanistan didn't develop one in the past twenty years, because the occupation couldn't be assed to.
The level of support that the Taliban has in places like Kabul is pretty darn low, the problem was always that none of their opposition was ever strong enough to effectively oppose them mainly because of just how much external support the Taliban gets from Pakistan and many other regional actors.
The Northern Alliance successfully opposed the Taliban for nearly a decade, its quite likely that some new iteration of it would also successfully oppose them today. (Tho in the past and most likely present that opposition would more likely to be some mutually agreed on stalemate with some periodic skirmishes than a live opposition).
But until you deal with Pakistan the Taliban will always be there to stay.
No form of social engineering would solve this, the tribal areas didn’t had night clubs or girls robotic teams under the US occupation either. And other than in Pakistan that’s where Afghanistan was lost.