The 787 *must* have fuel tank inerting - along with two other EMI protection schemes - interference-fit fasteners and metallic earthing paths in the wing skin. It needs these because of the very poor electrical conductivity in CFRP and cannot be certified without them. This is not just a lightning strike issue, it is to cope with component failure currents also.
Airbus have the same requirements on the A350. Implying that Airbus have a more lax approach to limiting in-tank ignition is incorrect.
I also recall that hull losses attributed to lightning strike include two Boeing a/c and no Airbus airframes (
Aviation Losses from Lightning Strikes - National Lightning Safety Institute)..