So, the current ‘joke’ is, buy a brand new vehicle, wait a month for its value to appreciate, then sell it back to the dealership.
My guess on the reason for the pricing increases is several factors:
At the beginning of the ‘shutdown’, it affected auto auctions, where dealers obtain a decent amount of their pre-owned inventory, besides trade-ins.
Actual manufacturing shutdowns decreased new car outputs
The rescue package allowed for a substantial jolt for vehicle financing, and it is not uncommon now for people to finance a car for a 6 year term. There are also 7 year terms, now.