This PR is not related to user privacy. That already exists by default on lightning since even a node operator can by definition never know the first hop or the final hop of any payment. They only know what passes through their node. They cannot know the sender or final recipient.

This PR is meant for node *operators* to be able to purge internal node data— ie, amounts forwarded and number of transactions forwarded. This information could potentially be used against the operator, for example to assert tax liability, AML non compliance, unauthorized money transmitter, etc.

TL;DR intended to improve privacy for node operators, not LN users— since users already have excellent privacy by default.