But in California companies can (apparently) still require you to chat with a real person online and thus still need to do everything synchronously, wait in a queue, and argue with them for several minutes before they will cancel the subscription.

Personally I think that any time you grant permission to anyone to bill you automatically on a recurring basis, you need to be able to revoke that permission. This ought to be a fundamental mechanism of personal banking that you ought to be able to manage on your bank account online. It's astonishing to me that your bank can't even tell you all the ongoing recurring payments that are permitted on your account (or if they do, it's an ad hoc implementation that tries to detect recurring payment amounts, vendor names, etc.)

Which is great for California, but what about everyone else?

I think that was the point of the comment.