> No, this is specifically for the case of someone intentionally signing up to receive the texts first.

How do they know I consented vs the person who had the number prior to me? I recieve texts I didn't sign up for all the time for companies I've never heard of for people with names and addresses that are different than mine.

I really feel the burden of consent should be on the sender vs the receiver.

Think of it this way, the receiver must carefully read what they have received in order to correctly opt out but the sender can just run a regex for "STOP" and call it a day. The more difficult burden should be on the sender. They should have to validate every message received to see if it is requesting to opt out. Put another way, the consent is retracted even if your regex didn't detect it.

When it comes to sex consent doesn't work that way; "She didn't say the safeword I texted her a year ago your honor so I had consent!"