My uncle was the lead night shift mechanic for TWA in 1996. That evening he was off. When I asked him what he thought of the fuel tank theory he said "no way".
That's because millions of planes, cars, trucks, tractors, heavy equipment, etc, have electric pumps, sensors and related circuitry in their fuel tanks also. These tanks contain all sorts of fuel blends, from #2 diesel to winter gasoline to gas-o-hol blends. The wiring harnesses to these tanks often contain other circuits such as tail lights etc, and are much more poorly maintained and inspected compared to a 747.
Your uncle never saw a Boeing, a Ford, or a Chevy blow up while going down the interstate.....and neither have I.