Forget retooling costs, the big 3 are paying billions a year in CAFE fines for not meeting fuel economy regulations set by the federal govt. Ford is “only” at 1 Billion why chrysler is at 3 bil and GM is estimated over 5 bil. Thats each year! Ford CEO has outright stated he would rather spend on infrastructure to build and sell EVs than to keep paying Billion dollar fines (that go in the pocket of tesla and rivian as subsidies). So really what they spend on “retooling” they save in fines. I dont know if chrysler and GM have made formal statements about CAFE fines and EV plans but there is give and take to help automakers transition and Im certain GMs $5 billion dollar fine for a year would cover a lot if not all the retooling costs.
You should probably compare the EV9 to and F150 lightning or Rivian R1S/T and not a model Y. Also Tesla over estimates what range is in their vehicles. But to your point yes a Tesla is very efficient due to their shape in comparison to the less aerodynamic vehicles that are SUVs/trucks.