You are correct. The real question is why all the weapons were not removed or destroyed when we left Afghanistan? C4 for the artillery pieces and diesel for the warehouses of arms and ammunition aircraft and vehicles. There is only one logical explanation. Joe Biden wanted the Taliban to have these billions of dollars of weapons. That is giving "aid and comfort" to the enemy. Joe Biden committed an act of treason.
They have serial numbers, should not be very hard to trace origin. I’m not jumping to conclusions, but tracing the numbers will probably show multiple paths on the weapons.
But it is clear that some of them came from US production.
Yesterday I saw a thread that showed many that came from Gaddaffi’s stock.
We will see, probably. If a lot of the are from USA, we will never see that in print.