They might have had poor taste in house guests (which cost them a generation of war) but they are the legitimate government of Afghanistan
Northern Alliance must've been some pretty bad dudes too.
Ironically, if we want to go by your definitions, Afghanistan doesn't exist, therefore nor does a government. It's a construct of the West.
In the reality you're trying to suggest, that entire region exists as a bunch of regional tribes, perhaps more like the Emir(ates). Unfortunately, they are not United.
The US mandate against the Taliban was to prevent Al Queda from using the Taliban’s military infrastructure.
The Taliban was never officially deemed a terrorist organization, or a non-state enemy combatant, and only Pakistan was ever involved (instructed) to arrest or detain Taliban operatives and leaders. (That being said, due to the consequence free nature and lack of oversight, Taliban operatives were targeted and killed fairly indiscriminately especially by the drone pogroms.)
Despite the lack of distinction made to the Americans who were needed to remain scared and confused to support the expensive operation, the war time and diplomatic efforts mostly distinguished between Al Queda and the Taliban.
Its just US news and leaders who were playing US and NATO’s people for two decades straight.
This discussion isn't about the tribal nature of that region, which is valid. You’re absolutely right that the “government” and even the nation state concept can be ignored there. Unless you are a woman with different aspirations than what the governing authority says. But thats not this discussion.
Last I saw we just surrendered to the Taliban, freed 5000 of them including the current leader, the insurgency is now the de-facto government of Afghanistan, and we recently had a high profile journalist hacked to pieces with a hand saw in an embassy and didn't do a damn thing about it.
How is the war on terror "essentially won" in your eyes?
Also, for your bit about being hard to believe - the agency reported it themselves, so you're essentially saying you believe nothing except that which conforms to your existing world view. Not sure what to say about that.