This has been possible since at least the mid 90's. We used to update the firmware over the air. We could change any settings on the phone, but would only do

This has been possible since at least the mid 90's. We used to update the firmware over the air. We could change any settings on the phone, but would only do so when required to keep the phone operational. Anything beyond that risked customer support calls and bricked phones. And yes, we sometimes bricked phones. We even had the ability to brick phones intentionally, if stolen, but that feature was never used by customer support for fear of bricking the wrong phones. Some years later I was at a company that could rewrite any part of your phones OS over the air. They did some fairly clever things that were barely documented by the vendors. I can only imagine what is possible today.