Just a feature that would be nice to have at some point, that's why it's been put as "Low".
We've had this for a short period of time sometime at the start of Miraheze, which was hosted by @Southparkfan. It displayed how many messages a user sent, how many were helpful, etc.
There's no IRC tag on Phabricator (and I don't think it would be necessary) so leaving this untagged.