Not sure I see the overall win here. The CAFE standards drove efficiency in vehicles, its why we don't have 8L V8s getting 9mpg in family SUVs. Sure, not everything is a win, I see little to no difference between the 6.2L in my Gen 1 Raptor and the 3.5 in my Gen 3. But in general, it reduced our demand on fuel.
By introducing electric and hybrid cars, it further reduced demand.
Now, we look at the supply and demand curve. If there is no mandate to ensure we do better on mpg or provide alternatives so the rest of us can have the available fuel, the demand will increase. If supply stays the same, hate to say it, but price goes up. Even with more american oil supply, capitalism will ensure the price goes up. No one is working to make life cheaper for you. Don't kid yourself otherwise.
Oil prices won't go down except unless we end up in a recession.