What exactly goes into the tank when the fuel is consumed or transferred then? It’s not under a vacuum.
Fuel fumes and air, at the atmospheric pressure of flight. Not a favorable mix to support combustion.
Many sensors for fuel do not have the electrical elements in the tank.
Most large aircraft do not measure volume in the tank. They meter the volume that has been consumed in a fashion similar the way fuel is metered when you purchase it for your car; and, that is mechanically subtracted from the amount of fuel that was loaded.
Another matter: TWA 800 was fueled with JP4, which is not a particularly volatile fluid.
Do you people actually believe that the engineers never thought of these problems when designing the instruments?