I tried to look up how much power these self driving systems are pulling, but it looks like that will require a deeper dive. The only results I got from a quick search were from 2017-2018, and the systems were pulling around 2 kW. I’m sure that’s come down in the 7-8 years since, but I don’t know how much.

I think you’re right on the lawsuit/upgrade cost. They are on the hook to supply Full Self Driving to all the buyers who bought the option. It’s clear they’re not going to be able to provide it. It looks like there are several class-action lawsuits currently underway.

The power draw to process the LIDAR data is negligible compared to the energy used to move the car. 250-300 Watt hours per mile is what it takes to move an electric sedan on average. You might lose a mile of range over an hour of driving, and that’s if you add the LIDAR system without reducing the optical processing load.

LIDAR sensor housing can be made aerodynamic.

While it’s true that LIDAR was more expensive when they started work on self-driving, it doesn’t make sense for them to continue down this path now. It’s all sunk cost fallacy and pride at this point.