The 787 has a copper mesh embedded in the carbon fiber matrix - the wing, fuselage, pretty much everywhere. In addition - due in part to the uncertainties in the lightning characteristics of carbon fiber - they added a metallic copper foil to the inside of the wing skin. Once they had real aircraft structure to test and analyze they were better able to quantify the lightning threat. Then:
In December 2018, SAE revised the zones based on data from reports of more than 1,000 lightning strikes on aircraft. It found that the area aft of the engines — designated Zone 2 when the 787 was certified — was rarely hit, and so changed its classification to Zone 3.
Combined with the zone change around the engine pylon, it was determined the foil was no longer needed, that the copper mesh along with the nitrogen inerting system provided adequate protection against lightning strike.
I worked with Tom Thorson - the FAA specialist quoted in the linked article - and he's reasonably sharp. But he's a Propulsion specialist, not a lightning specialist. I worked some aspects of lightning protection for 20 years, but my lightning knowledge was a small fraction of that what the Boeing (and FAA) lightning experts knew.
I used to say - somewhat joking - that I knew enough about lightning and lightning protection to be dangerous. Based on some of the posts on this thread, it appears ignorance is even more dangerous.