We have had drive by wire in forklifts for several years, even steer by wire. While there are problems that have arisen, most of the problem is between the steering wheel and the seat. One feature on electric lifts and some combustion lifts, is a switch on the brake pedal that not only operates brake lights, but also disengages the drive. I wonder if automakers would not be smart to look at this simple option......
Most transmissions now are shifted by electric solenoids, but the ony way I can see for the transmission to fail to disengage and the accelerator to fail all at once would be wire harness shorting or the ECU going out.....the harness would be obvious, and it's unlikely the ECU would fail in two areas at once.
I'm not doubting that folks are having trouble, but it seems to me they are panicking and not, as stated, using common sense.