It’s the easiest solution that looks like you are doing something about traffic.
Terrible answer: make the most dense areas car free. You must park outside them and use alternate transportation. Exceptions for government, maintenance, and delivery.
The section of the 405 that they are looking to expand is the 2 lane section that was built for a fraction of the traffic that now uses it. The 5 lane 101 that and the 6 lane I-5 that are connected by the 405 will see massive drainage issues resolved by having better throughout. The only people complaining about this are the rich people who live in those hills hosting the expansion.
Fuck the NIMBYS. Make the lanes.
When your only tool is a hammer, everything looks like a nail.
How is California so bad at traffic? Texas managed it, even the Katy freeway flows.
Is it intentional? Do they just have the wrong priorities? Is it geography? Why?
Its about economic success and density. You can build really low density environments where people drive fast but really far, so travel time limits traffic. Go any higher density, while being prosperous, and traffic increases to match road capacity for any practical amount of road you build.
People want the density because it enables greater specialization and the prosperity and higher wages which come with that.
Texas has dense parts too, like parts of Dallas. It’s not a good excuse.