With general respect to what is written, I don't like the "it's encrypted so it's a non-issue" approach. Sure, data has to be exchanged for many operations - including crypto transactions - but the best model of privacy is when the unnecessary data does not get sent anywhere in the first place.
Encryption can and eventually will be broken, it can also be implemented wrongly, the devices themselves can be hacked or taken by somebody etc.
Not sending the data always beats sending the encrypted one as far as privacy is concerned.