It’s a deal between the US and Taliban. That’s it. Forget the US, they are there in spirt onlySo the current deal is simply to allow the US to cut and run, and allow the Taliban to focus all their efforts and energy against GIRoA. You can understand why GIRoA hasn't bought it.
The biggest hurdle to fighting - the US presence - is being removed.
Now the conditions should be there for the Taliban/Government to talk. But they can’t. Cannot make it any simpler than that.