People who worked their entire life in an industry and became experts on it, then become regulators for the same industry, have incentives to favor their industry, sure. But who else should be regulating the industry if not the expert in that industry? If you get someone who is not an insider, wouldn't they just fail at regulating, because they have no idea how it works? Also, the people who put someone in that position, isn't there a chain of accountability there? There are many people working side by side with the "evil person trying to enrich themselves". Bad acts come out. Incentives tend to balance each other out. It's not wrong that part of a regulator's job is to find a balance as to not destroy an industry while regulating it.
Is it really not how things end up happening? We must be living in two different realities. The greater the power, the higher the likelihood it becomes corrupted. With such a high incentive to give into corruption, you can’t just hand-wave it away with “but I’m sure it gets balanced out by something”. Your local family doctor might be a good enough person to help you get better without expensive drugs, but the head of a large institution? Fat chance.
An institution's whole point is to be a system where you don't have to trust individuals. It's a way to deal with complex nature of our reality. People should really learn what institutions are, how they function, what accountability mechanisms they contain, instead of blaming them based on conjecture. "Look, this bad thing happened. And this person has this bad incentive. Now we know the whole story." We don't.
People place trust in faceless institutions all the time. That's why you sit in a box that produces about 50 explosions per second when you drive a car. I don't think you would've gained much by being comfortable with the character of your car designer. If you think building cars is complex, laws and regulations are just as complex. And it takes teams of lawyers, hundreds of pages of documents, and a lot of data to figure out what makes sense. But it's easy to armchair-judge all of that as "just some faceless institution".
> what forces exist to prevent them from being corrupted?
Why are you right now not stealing from your work, or vulnerable people around you? Why are you not trying to screw over everybody you meet? Those forces and more. There's a lot of scrutiny built into most institutions.
> the growing cynicism in institutions is because of evidence of corruption
I don't think we use the word "evidence" the same way. Having perverse incentives is not evidence.