But there is no inequity or conflict of interest here. None of that about being trapped in a capitalist economy is to the point here. He has probably a couple million dollars in his bank account that wasn't there before, and the deal was to not talk publicly about internals (which includes promotions process, internal motivations and decision-making, etc).
"Yes, I agree to not share internal info, in exchange for this money. And by the way, I will still share internal info, because inequity."
In other words, consider someone's perspective who has society split into two camps: the people who do all the work, and the corrupt elite that make their living through theft and oppression. In such a world, signing a contract with an employer (i.e. capitalist i.e. elite) is more of a practical step than a sacrosanct bond. There's a level of "what's reasonable" and "what legally enforceable" beyond the basic "never break a promise" level you're working at, IMO.
No ones endorsing publishing trade secrets randomly, but you're treating all disclosures like they're equivalent.
I'm not saying you are wrong per se. But if you don't see why employees are willing to act in this way, you don't see how employees feel about being trapped in a system where no matter how much you are paid - you are ultimately making someone else more.