I am not seeing the value in discussing privacy at the protocol level. Sure I share what I want to share with the other party but that is not where the privacy

I am not seeing the value in discussing privacy at the protocol level. Sure I share what I want to share with the other party but that is not where the privacy violations occur. The host of the service (like FB) will suck up all data and use it to mine info on me. That is where the leak is.