With this content being cached by nginx, these queries shouldn't run
more than once every 15 minutes (or whatever your content cache is set
to), as far as I understand it. I have verified HIT/MISS via the
returned HTTP headers. Perhaps this is more of an issue on large
instances, but rather than this data just missing for all instances,
perhaps a control panel option could be added to enable/disable this?
Misskey nulled these stats as part of a performance issue:
https://github.com/misskey-dev/misskey/issues/9505 and committed changes
at c5cfbd99d0