Note the charred cell phone on top of the pile with another cellphone among the other stuff, some stuff did get burned.
Jacket isn't too damaged and the type of weapon they used is known for dicing targets into chunks rather than reducing to cinders.
Vehicle is still on fire, likely the only fire resulting from the vehicle's fuel itself being ignited by the impact/friction of the strike
This isn't a "9/11 hijackers and the indestructable passports" situation. This was a targeted strike intended to minimize collateral damage.
Retrieving the pictured items may have been a bonus goal of the strike on Soleimani. Maybe John Kerry's got a few texts on the phone?