This has nothing to do with Pakistan/India/Russia/China.
This assassination is a power play between Taliban and US to remind people who is still the boss in Afghanistan. Taliban want to gain leverage over US in talks and exposing fragility of Kabul is a good way to do it. Taliban are basically reminding US that they can kill US puppets in Kabul anywhere anytime if US does not agree to their demands. Kabul is a house of cards that and all it takes is one rock from Taliban to shatter that glass house of US puppets in Kabul.
Just because Taliban did not use magnetic bombs in the past does not mean they would not do it in the future.
Taliban are not stupid. They have been watching and learning from the US itself.
US thought they were so cool assassinating Soleimani but now they have given all their enemies the same idea and that includes the Taliban who now see assassinations as a very effective way to demoralize the enemy. Now US own playbook will be used against them by the Taliban and other groups.
It totally makes sense why Taliban would do this, they want to give knockout punch to US to gain more leverage, this assassination obviously worked and Taliban sent a clear message to US showing who is still the boss in Afghanistan.
