[squeaky-clean]

This view assumes they actually do their job for the good of the people and also happen to profit off of what they privately learn in doing so. Instead of making decisions based on what can get them the better payout or preservation of their investments.

To make it a programming analogy, to someone who has no clue about coding a yearly bonus to each developer based on lines of code written sounds like a good way to reward the more productive developers. But anyone with a couple days experience realizes how trivial that system would be to game.

[celtain]

A member of congress voting for $10B of useless defense spending because they're heavily invested in the relevant aerospace company isn't committing insider trading.

Perhaps this is unnecessarily pedantic, but what you're describing is a "conflict of interest" problem, not an "insider trading" problem. You can have either problem without the other, and depending on how you crack down on insider trading, it could be completely ineffective at solving the conflict of interest problem.