“Seeing what changes are coming” is insider information.
That’s not insider information following the legal definition in the US. That’s why people want to make special laws to prevent this.
It’s not insider information to buy or short a stock knowing you’re about to do something that will impact a company.
Exactly. The corruption is systemic and structural, rather than individuals' moral failings. (Though of course there's plenty of the latter, too.)
By having lawmakers as peers, you’d have a natural feel for what laws have momentum, who would benefit, etc.
I’m not ruling out corruption, just that assuming malicious intent often masks underlying dynamics.