All of the big automakers (Ford, GM, Chrysler, Toyota, Honda, Mercedes, BMW, Audi, Fiat, Tata, Jaguar, to name quite a few) have way more experience manufacturing cars than Tesla does.
In frames, stamping body panels, final assembly, yup. I think Denny is more concerned with the parts of the EV that are not shared with an ICE car. Induction motors, battery packs, motor control, charging control, etc. Motor control alone can have a big impact on performance, on battery life, etc.
One other thing to mention about EV vs. muscle car. Driving an EV has the throttle response that will rival pure-bred race engines. Its not just that the ICE needs to rev to produce power. Open the throttle always causes a lag in output, even in the best engines. When you open the throttle blades it WILL cause a brief drop in intake manifold air velocity until the engine catches up. With an EV extra power delivery happens AS YOU ARE MASHING THE THROTTLE DOWN, NOT A BRIEF PAUSE LATER. It really is a neat experience.
Bill
I tracked a 1992 Corvette (LT-1 6-speed) for 3 years, a Honda S2000 twice, and raced shifter karts for 4 years