I love how you compare Bitcoin to SMS.

I could send an SMS to a number, and anyone could be reading it, and I could even have no control over whether or not the message is seen by others, or even delivered.

When you send Bitcoin to someone, you actually sign over ownership of that data. I send you 1 BTC I actually authorise to transfer ownership of that 1 BTC from me to you. And I know only you get it, only you can access it (unless you shared your access or you use someone else's access).