You basically want to remove anyone competent enough to think a few years about an issue and develop reasonable strategies to deal with it to be removed from the system.

Even if I would agree with the goal you won't achieve it.

The SC's have no reason to listen to the Chamber of Commerce. They need no election funds or advertisements and they will not serve more than one term.

Again naive. You don't need to pay politicians money that they listen to experts who spend a lot of time thinking about a specific issue in detail. Listening to experts who study a given subjects for years is what any reasonable person does. That doesn't automatically means that one does everything that one hears but the ability to actually spend a lot of time to build experience in a subject usually helps when it comes to explaining how to do things.

If you are a bunch of 10 random citizen and 10 people with PhD's in medicine and you want to overhaul the medical system it makes very much sense to listen to the various stakeholders and their perspective of how a proposed law might effect them.

If you design a system to avoid letting stakeholders speak with the law makers you are going to end up with laws that do things that the people who wrote the law didn't foresee.