Your point #1 was right on the mark. Initially, many people did welcome the Taliban because they promised an end to the chaos that existed before. However, as the Taliban became more and more repressive, they became feared rather than respected. You can't build a stable government based on fear and repression. When Kabul fell, I heard one radio announcer say "Drop your burkas and boogie" as women came out of seclusion, dropped their burkas, and people listened to music. Many people had old scores to settle as well. A lot of those Taliban fatalities came from people sensing impending liberation from tyranny. This was and is especially true for the foreign Taliban members. It's bad enough when your own people are oppressors. It's much worse when foreigners are doing the oppressing.

In addition to the good work by the BUFFs, don't discount the close air support that became possible with Special Forces troops and perhaps some Forward Air Controllers on the ground. This allowed for much more effective targeting of Taliban positions.

Aerial bombardment didn't win by itself, but it does have a way of weakening and demoralizing an enemy, especially when he can't get resupplied. Those Russian supplied tanks and other weapons were put to good use by the NA. Let's hope they stop shooting once the Taliban is gone.