Pick-up truck availability is indeed often better and better valued than other car types at rental agencies. The new RAM type pick-up trucks in some of these rental car fleets are actually not that far removed from feeling like a big SUV for the driver + 4 passengers.
A sign of the times with rental car availability prices: the Amex offer for Silvercar rentals is $100 back on a $500+ rental. 20% back is nice, but the threshold set at $500 for triggering the $100 offer credit speaks to the rental car pricing scene this time.