Moscow is trying to settle old score but America is America.
Sort of.
Although Afghan Taliban have become strong again, they understand that the only force which stand in their way towards retaking Kabul
is the American troops stationed there.
Although Afghan Taliban and US are having conversations in order to decide the future of Afghanistan, the former dispatched a
1000-strong contingent to occupy Ghazni not long ago
. Local defenses of Ghazni collapsed in just 2 days but US dispatched its forces to rout Afghan Taliban from the city. Afghan Taliban suffered about 250 casualties in this fight alone - largest between US and Afghan Taliban in a span of years. Not sure what Afghan Taliban were thinking in this case because they have unspoken truce with US under normal conditions.
Details here:
http://time.com/longform/ghazni-fight-taliban/
Even though Imran Khan opposes American intervention in Afghanistan, even he does not have the power to close Pakistani supply route. Afghan Taliban understand this reality and therefore they have no choice but to negotiate with US.
One thing is apparent to Afghan Taliban though; American
political will to sustain operations in Afghanistan is
eroding because Afghan government turned out a dud. Therefore, Afghan Taliban believe that victory is in sight, and are surging with confidence. However, they are hardened and patient.
Let us see what becomes of Afghanistan. Whatever it will be, Afghan Taliban and US have the ultimate say in this matter. Pakistan is OK with this because it has to work with Afghanistan irrespective of who controls Kabul.