$100,000 USD, $200,000 USD, and $400,000 USD, you will pay:
$32,000, $69,000, and $159,000 in taxes in California.
$28,000, $73,500, $169,000 in taxes in BC.
But that's just income tax. There's also Social Security/Unemployment Insurance contributions. In the US, 13%[1] of your salary up to $130,000 will go to social security contributions. In Canada, 10% of your salary, up to $40,000 USD will go towards the CPP and Unemployment Insurance.
So, at the $100,000 USD salary, you will pay $45,000 in taxes in California. In BC, you will pay $32,000 in taxes.
At $200,000 USD, you will pay $86,000 in taxes in California. In BC, you will pay... $77,500.
At pretty much every tax bracket, you will pay more taxes in California, and get less for them, then you would in BC. As it turns out, maintaining twelve super-aircraft carrier groups is expensive.
Mind you, BC is not all flowers and roses. The provincial government runs the place with all the integrity and forward-thinking of a banana republic.
[1] Yes, your employer pays half of it. That money would have otherwise gone towards your salary.
The highest marginal income tax rate in California is 52%.
For that tax money, in Vancouver, you will also get free* healthcare.
In San Francisco, you will get... Actually, I'm not sure what you'll get. The biggest prison system in the world? The biggest military in the world?
* At the higher tax brackets, you will need to pay a $1,800/year MSP premium for a family, or $900/year for an individual.