This topic gets complicated fast but it boils down most simply to:

1. Options in representation. California is essentially a single-party state. Switzerland has substantially more options in this regard.

2. California is freaking huge, Switzerland is not. Because of this, you have dramatically different interests between different regions in California contrasted with more homogeneous needs in Switzerland.

3. The population of Switzerland is not nearly as diverse as California. They speak several languages there, but overall you have a group of people with very similar cultural and historical values.

4. This point would require a small novel, but in essence California abuses the system to go around the process rather than go through it. You could describe this as the contrast between cooperative governance (Switzerland) and adversarial governance (California).

In short, if we stuck with George Washington's suggestion to lower the maximum size of congressional districts to one representative per 30,000 people, California might be in better shape. It probably would have also been beneficial to listen to Alexander Hamilton when he called parties “the most fatal disease.”

Points 2 and 3 don't seem to be things we can modify. Are they barriers to an effective implementation, or will the increased size + diversity be more friction but not a blocker?

For points 1 and 4, those sound like symptoms to a more rudimentary problem. I don't know what that problem is, but my guess is its something systemic and structural.

Points 1 & 4 could be solved either via elimination of the party system (unlikely) or if one of the several initiatives to break up California succeed (also unlikely). Simply put, the problem is that when you have one party in control there's very little incentive for them to work cooperatively with the people.

Points 2&3 are could also be solved by dividing the state up so that each region could self-govern. Given that this is unlikely, I have a hard time imagining a solution. It's extremely hard to make "city folk" understand what's going on in rural areas, and vice versa. Worse, our current political climate is such that demonizing the other group is seen as a morally acceptable thing to do, almost always without really understanding them in the first place.

The first step to solving these problems in California is to close the political divide and get the people to work together to establish better representation.

Isn’t it generally accepted that increased diversity in a decision group leads to better decisions? Splitting the state up would draw territory lines where there are only cultural lines currently.

Eliminating unions and splitting the state don’t seem to be feasible options. What else can we do, is there something less radical that can chip away to close this gap?

> Isn’t it generally accepted that increased diversity in a decision group leads to better decisions?

Perhaps evidence to the contrary, it seems widely believed that the governance of most Nordic countries and other nations like Switzerland result in (much?) better outcomes than the US. There seems to be something of a fascination with those nations in terms of their social support systems and the like. Interestingly, those nations are substantially more homogeneous the United States.

> Splitting the state up would draw territory lines where there are only cultural lines currently.

I don't think it's a given that this is a bad thing. The principle behind states and counties is that the populations can govern themselves in a way that fits their values. An extreme case, an Amish population that has gathered in a particular region, would probably not feel great about being forcibly assimilated into another group's social or governmental structures. Their beliefs are so disparate that it's difficult to imagine they would be able to find common ground.

> What else can we do, is there something less radical that can chip away to close this gap?

Acceptance of other people's values without demonization is key. The US has devolved into a state where the opposing political belief is now seen as a flaw of their character or morality. You see that Even on a site like this where the average commenter is better educated than the average citizen. (The comments about Trump supporters all supporting segregation as example).

To fix this, we need to break the echo chambers that perpetuate these beliefs. Unfortunately, because of the current polarization, it's difficult even for an elected official to agree with the opposition about any issue without reprisal from their own party or the voters.