Regulation and control is by its nature an adversarial relationship. You cannot be an effective adversary if that will compromise your ability to be an advocate or employee of whomever you're regulating.

Just as an auditor doesn't need to be a domain expert to audit a companies books, a regulator doesn't need to be one, at least from an industry POV.

The "employ a hacker to catch a hacker" methodology of hiring is fine, if your hacker is going to catch other hackers. If you're actually just hiring thieves to help themselves to all they can carry in their pockets, then their expertise really isn't relevant beyond their own self-serving exploitation of that knowledge domain.

Absolutely agreed, but the industry insiders have to be impartial and use their knowledge and experience to come up with a decision.

The question you have to ask is what's the motivation to approve (or deny) a given application or law? If it's because it's the 'right thing to do' (broad term I know) then fantastic. If it's to 'help out a mate' or 'it may be the right thing to do, but meanwhile there's incentives for me to vote this way' then that's where integrity has to be questioned.

I would counter that anti-trust decisions are not industry decisions, but population wide decisions and hence they should be made not by industry focused bureaucrats but by more accountable general politicians.