> And battery packs have cooling systems too. So no savings there.
That's not quite true. At the very least, EVs require a much smaller radiator, if it has one at all. Some EVs don't have cooling at all (Nissan Leaf), although that increases degradation in hotter climates.
I think his point stands.. An ICE engine weight at least 200lb. With transmission it could be up to 600lb. The Model S engine is 70lbs.
You "only" need to halve the weight of a Model S battery for the drivetrain+battery to be in the same ballpark as an ICE drivetrain as far as I can tell.