No good reason to believe him or take him seriously.
I have been a participant in this fight for 20 years, on the private industry side. Its not just Wray, its a generation of IT security organizations, not limited to the FBI.
Wray is right, or likely to be right. There has been a long technological war about getting past air-gapped control systems.
Read up on Stuxnet. Thats the sort of thing he’s talking about.