Thank you for your input.
Your point of view is really interesting and I think we should take it into account.
On the one hand, recording private messages is a serious privacy violation, these are sometimes used to target advertising or are shared with third parties known for abusing their users’ privacy, or they could be accessed by unauthorized third parties during a data breach. These reasons could justify the blocker classification to be honest.
On the other hand, I agree with you with the fact that some services don’t seek private communications but rather a safe community. That is for instance the case of Discourse, the open-source software running this forum. This issue reminds me of a post in another topic closely related:
The solution found for the topic above was to create a point linked to Terms of Service; Didn't Read - Phoenix. Perhaps each reviewer should choose either Case 239 or the foregoing case depending on the nature of the service?