Here is my view

This stuff isn't magic

The real problem here is that every single electronic device would have to be tested with every aircrafts' avionics in order to verify safety.

Any radio receiver* will contain local oscillators which create mixing products. These mixing products are designed to be attenuated but they can still cause mischief. Clock circuits in computers/cell phones etc. also generate RF.

Interference from things like DVD players can probably be ascribed to poorly shielded motors or motor controllers.

As aircraft wiring ages, connectors work loose and/or corrode. Inadequately fastened connectors can act as a primitive detector that allows stray rf to enter the avionics system.

Without getting into specifics of the above mentioned incidents, it is probable that some of the cases described can be ascribed as much to avionics problems as to the consumer electronics device (I am thinking about the Nuvi causing interference to the CRJ--the first thing that I would check is adequate avionics grounding and that the avionics shielding is properly installed).

As a practical matter, when I fly, everything is disconnected below 10k and during those rare times when flying above 10K in IFR condx. Above 10k, I give the cockpit crew enough credit observe if something is not right...especially if they have outside visual reference. All of the cockpit electronics is redundant and, short of a thermonuclear event, it is unlikely that everything will go south at the same time.

P.S

The claims of the poster who state that he has flown a large number of flights without incident need to be addressed. Avionics interference is a low probability event. Non-interference might just mean that, whatever the number of segments you have successfully completed, it is not enough. If you fly more, you might observe the problem. This gets into Poisson distributions and extreme event analysis which is beyond the scope of this post.

*Local oscillators are associated with superhet receivers which are found in consumer electronics. Regen receivers do not have local oscillators and do not generate mixing products but they have other problems.