If you buy the hardware you should be able to turn it on. Jail breaking is fully moral in that situation.
The self driving is software that uses the hardware so should be paid for IMO. You should also be able to use your own software that’s open source on the hardware you own
Running your own software to control the automotive part of a car is probably not legal, since I assume the process of making a car street legal should requires an audit of said system.
Any software that passes whatever local safety standard should be installable (or software that doesn't pass if the car is not being used on public roads).
Otherwise the car is not being sold, it's being rented, and all the advertising that says anything about buying is fraud.
Good luck getting a homebrew OS for tesla cars to pass those tests. I don't even know how that would work. I'd be curious to know what would happen if you would try to register and get a car through the TÜV for example that runs on custom firmware.
Well-developed software built by professionals to industry standards and capable of doing a very important job effectively. And homebrew. You might be surprised at what sufficiently motivated nerds are capable of.
Homebrew software is unofficial/non-commercial software for systems which were originally set up with proprietary software (like gaming console or in this case car OSs).
It's similarly hard to make an airbag or seat belt, but you can still undo the bolt without the manufacturer in another country bricking your car without any considerations of your local laws.
Tesla is subject to some oversight by the National Highway Traffic Safety Administration. They recently forced a recall when they weren't satisfied with Tesla's software.
Does Teslas still have a disclaimer that the self-driving features aren't self-driving and that if the driver is using the self driving features and there is an accident Tesla can't be held liable?
If it was a matter of installing software on a laptop or phone, I'd agree with you, but installing software on a vehicle that can run over people is another matter, disclaimer or not.
Just like some cars are street legal and some cars are not, some software should be street legal and some software not. If the 3rd party software has been cleared by regulators for your Tesla, I'd be fine with it.
I did read it. They opened an investigation like 5 years after The Model S was released and people have died. Now, 6 years after that, something actually happens. 6 years of more accidents.
The same could be done with 3rd party software so there's no difference and it's not the same as the car system being regularly inspected.