No, it is not banned you are correct. What is "banned" is setting open beverages on the pedestal, I along with many other 121 pilots have caught he!! for setting a coffee or soda or even an open bottle of water on there where all those important electrons are running around. I'm sure Chris has seen the same thing.
I fly freighters for a living, boarding the 747 in our main hub I noticed the floor inside the L1 door was very wet with deicing fluid. Right behind me on the steps were mechanics and they proceeded to open the E&E bay to "dry it out" because ground support had deiced the airplane with ALL the doors open. Luckily it had only filled the drip tray, but if that wasn't emptied it would have poured on the avionics when we rotated. It doesn't have to be electronic to interfere.