schweizer gotcha, that makes more sense. If you understand the phrase "mutual respect", you understand that it means there are two parties that respect each other with no other parties involved. "Mutual consent" in this setting is very similar. The two parties are simply two apps that are mutually consenting to communicate with each other with no other party (being you) involved. It's not mutual consent between you and the two apps, just the apps by themselves.
There are plenty of legitimate reasons for this that I'm totally cool with. However, there are obviously times that I'd like this restricted. Thankfully, the GOS team is working on implementing app communication scopes to mitigate this.