It is the fault of the automotive manufacturers for buying into new-and-amazing technological feats in automotive powering only to later buy it out, make people sign confidentiality agreements and sweep it under the carpet then locking everything having to do with it into some safe somewhere. Lacking the R&D and implementation of better fuel efficient vehicles has saved car manufacturers billions of dollars. If they can make money on what they have, why upgrade. Musk, you are correct...but why have they not made an SUV that gets good mileage until only recently when forced to by foreign markets and competitors?
Answer: Money. It is cheaper to just sell what you have instead of coming up with something new. Oil companies pay them off and it creates an even greater incentive.
As far as my Explorer...I bought it because we have bad snows here. I like to drive up mountain trails that require light 4WD trucks where I can get away from the idiot population a little bit. But, because of mileage, I got rid of it and now drive my new Chevy Cobalt I got for just under $10k. It gets about 30mpg average, would have liked more, but again, what can you do? I didn't have $25k to spend on a VW with a Turbo Deisel. They no longer make Geo Metros. But, now, I can't drive more than 15 during snow or on ice. No more trips up the mountain roads.
So, yes, the car manufacturer's ARE restricting me, and it is time we mandate their output. We mandate food quality. We mandate healthcare quality. Why not mandate the quality of fuel economy from auto makers? Especially when it will better the US Market, lower oil consumption, and offer more of a selection to buyers who would like more than a sardine can to drive around in while considering fuel economy.
I don't even care about being green or global warming. I don't burn plastic or styrofoam. I don't do things unecessarily really to disregard our environment. I keep my heater low in the winter and air conditioner high in the summer. I try to keep my outtings to one trip with multiple destinations, without driving ot the store, coming home, leaving to the mall, coming home, going out to dinner, coming home...etc... But, my energy consumption is relatively small compared to most people. It is just how I live my life, it isn't really that I make a big effort doing it. My monthly utility (gas/electric) bill is about $35. Water bill is about $8/month. I only drive roughly 12,000 miles per year. But, I don't really even think about global warming. I only do what I do because it saves me money.
But, I really encourage mandating companies whose products are used on a huge scale to better their output when it is obviously lacking due to selfish reasons.
Now if we can just do the same with the fuel companies bouncing the fuel prices around like a basketball off the Royal Gorge Bridge.