The revolving door problem is mostly people coming back from a stint at a regulator to private employment at an salary that sometimes affect how beneficial their stint as a regulator was to the company hiring them post public service.

If that system was made one way so that people retiring from industry to government were forced to burn all "financial" bridges to the industry they were regulating by forcing them to accept a clause that they can newer go back especially not as a consultant a lot of those issues goes away.