I have an irrigation valve that turns the water on and off for the garden. It talks to the app via Bluetooth, and I’ve found that my phone has to be at least 3m away from it or it won’t connect. Any closer and the signal must overload it to the point where it can’t interpret it.

Not to discredit your example, but that's not exactly a car that we're talking about right? I would imagine more due diligence would have been done on the engineering side for a Bluetooth connection in a vehicle, versus a lawn sprinkler.

If cars were having that same problem of close distance issues that would be making the news, especially if it was a whole fleet of cars that that problem was happening for.