[Dylan16807]

> How about the software in the micro controllers in my car? Should I be allowed to modify that code too (if I mess up people could die)?

You're allowed to modify any other part of the car. Why should software be different?

> How about the software in my satellite internet radio transceiver (one rogue transceiver could take down the entire beam/jam the satellite)?

There can be some flexibility for the part of the code actually doing the transceiving.

Everything on top should be replaceable.

And radio is really a special case, because it's a shared commons that requires a lot of expertise and where one bad transmitter can cause problems for miles or more.