I expect there to be margin at every point in the system, excluding service. There is no money in servicing EVs and that is by design and part of the kill shot on ICE vehicles. The profit motivation related to service must be crushed to speed the mission. Traditional Autos literally will be illegal to operate in an EV environment. Lets take GM for instance, they cannot sell direct and they cannot afford to pay dealers to sell the cars for them and still remain competitive. Dealers will not sell cars they cannot make money from maintenance without other incentives. GM will have to die and come back as a different company that can sell direct. At which point ,their dealer networks will file suit. They really are really in a bad situation. Even if was legal to sell direct, their dealers will keep them locked up in court forever.
Tesla will have Margin on charging, solar and storage batteries. An average of 30% GM. Even Megachargers. How do I know this? because Pay 4c/KWh for residential solar with net metering, which is also available to Tesla in many states. Batteries for Megachargers will be mostly used to avoid fees related to spikes in demand.