"Top of the list was nation state hackers, he said, followed closely by international professional hacking groups that worked for money"
This is probably quite true, and he deserves some credit for putting terrorists at the bottom of the list on the reasonable grounds they have not (yet) achieved very much in 'cyberspace' actions.
But those top two in particular would make mincemeat of any backdoor or key escrow system and he really needs to get that point. Corporate/organisation-wide master keys simply don't scale to the government's desire because (a) nobody trusts them now, and (b) it would make everyone's device less secure when its found, not just a few hundred in any one department.
Defending the USA (or any other country's own) government and businesses interests means you need strong security, properly applied. Yes, it might make catching the odd smart criminal a touch harder, but it leads to less crime overall.