Rather than going after individual companies, seems like a nice solution would be federal legislation that says "All subscription services must provide: mailing

Rather than going after individual companies, seems like a nice solution would be federal legislation that says "All subscription services must provide: mailing address, email and phone number. Subscriptions can be cancelled by contacting the company through any method by including: a) request to cancel, b) name, email. Cancellation is effective immediately." Companies seem to respond very quickly when you forward legal code to them that they need to follow.