100% true.
The HMMMV uses 70 year old technology and is very basic, the MRAPs they had were the first edition, no more technical than the International truck chassis it is built on albeit with added armour, this model is on its 6th generation and doubt very much that any of these newer models where left behind.
The drawdown started in 2014 when OP Enduring Freedom ended and Resolute Support mission started, and since then huge numbers of vehicles and equipment had been shipped back to the US, Germany and other places.
I find it hard to believe that anything that was given to the Afghans will hold any value other than eventually scrap metal, and these will be left to rot away scattered around the country, as the Russian helicopters and armoured vehicles from the 80s are.
The monetary cost to US tax payers money is another story.