1) When Bob Lutz was the head of GM, the company was hemorrhaging money from fixed costs that could not be altered except by taking the company through bankruptcy. Tesla's fixed costs are very low and their losses are almost all R&D and capital investment. He either doesn't understand the difference, or he chooses not to understand the difference.
2) Tesla is the only PHEV or BEV that has not been affected by oil prices (at least in the US). The monthly plug in scorecard on insideevs.com (
http://insideevs.com/monthly-plug-in-sales-scorecard/) shows every car on the list with any sales above noise levels the Model S is the only one that saw any appreciable increase in 2015. The BMW i3 is the only other one I see had increased sales in 2015, but that was mostly because it didn't hit the market until May 2014. There were 4 months in 2014 where the i3 sold over 1000, but only two months of 1000+ sales in the full year or 2015. Tesla is the only car brand out there who has interest from people who aren't eco or incentive buyers. The Model S and X are competing head to head with ICE cars in their price range and winning on merit. The dip in oil prices may have slowed Tesla sales a tiny bit, but most people who can afford a Model S or X aren't going to worry about being able to pay for a full tank of gas on a big SUV either regardless of gas prices. The people who are most affected by gas prices are the poor driving a used car or a very cheap new car because they can't afford anything better.
3) Tesla is getting a reputation akin to Apple. Anything they produce causes a stir. The Model 3 will get a lot of serious looks from mid-range car buyers who would never consider any other kind of electric car because it's a Tesla and it will likely be not only electric, but have very good performance too.
4) Bob Lutz bases his experience on selling cars direct on an experiment BMW did when he was high up in BMW America in the late 70s, 15 years before anybody but a relative handful of geeks had ever heard of the internet. Selling cars is expensive, but the traditional model pushes the risk off onto franchised dealers who will lose the money on turkey cars nobody wants. That's why Lutz always brings this up, but most of the companies he worked for had a lot of turkeys dealers had to figure out how to move.
Compared to Tesla car, most cars on the market today are not very inspiring to the car buying public. Car makers are slowly adding new features all the time and tweaking things, but nothing has jazzed car buyers like Tesla has in a long time. Occasionally a new car comes along that becomes hard to get for a while and people scramble to buy them. Even a few fools end up paying more than the sticker price to get one before anyone else. But those are few and far between. Most cars won't move without incentives of some kind and it's rare for a car to sell for the full sticker price. Tesla has only had two incentive deals which only amounted to $1000 to the buyer, and the vast majority of Teslas have been sold to consumers at full sticker price with no discounts.
Tesla is in a position every car maker would like to be in, but most probably have never been that in demand, ever. Tesla doesn't need dealers because they don't need to maintain a large supply of cars consumers are tepid about. They presell most cars. Who needs dealers when you have customers knocking down your door with minimal advertising?
Bob Lutz fundamentally does not understand Tesla and some people listen to him because he's an old hand in the car business. I think he's also kind of bitter because his last legacy at GM was the Volt which he wanted to make a pure EV, but got talked out of it. His people convinced him people wouldn't buy a pure EV, and if someone goes and proves that decision wrong (which Tesla is doing), then his last project at GM is tainted and just a footnote in history instead of an advancement of the technology as it was intended. Lutz can't admit Tesla might be right because then he'd be wrong.