The revolving door argument is accurate, not thin at all, and a very important thing to remember when you have fine upstanding citizens like Meredith Baker getting appointed to office. The corruption goes from regulators to industry though, which is not the position that Tom Wheeler is in.
That does not mean that it's safe to appoint former industry lobbyists. Even an honest lobbyist has spent much of their professional life in close contact with, possibly friends with, industry reps, and the lobbyist's job is to regurgitate industry talking points. Believing those talking points, at least in part, makes a better lobbyist. Going from industry to regulation is less dangerous than the other way around, but the fact that Wheeler seems to be working out is likely a fluke. Someone of unusually strong character, at least for a person in his position (this is not a compliment).
As for finding someone without the ties to industry - this isn't as hard as you make it out. For one thing, why do they need to know all the details of the telecommunications industry before they even start the job? We like to pretend that this is a requirement for every position, but we have tons of CEOs, judges, and politicians who don't meet this standard and when they fail people love to jump on this as the reason. A much larger portion though, are successful. A CEO for example, needs to be able to lead first and foremost. If they can do that much very well, then they may not need to know everything about the company's products and practices before they start the job.