I don't know that much about the region, but the us-supported side had 20 years and lots of money to prepare for this day. I would assume if they enjoyed more popular support in the near past they would have built something that would less obviously be the losing side today, and people wouldn't have jumped ship so quickly.
The US built their side so as to maximally depend on them and then pulled support abruptly, while all but grovelling to the Taliban in public. There could have been no other result the way this withdrawal was done.
