The configuration variable $wgEchoHelpPage should be an optional interface message so that the help link can be configured without having to go through bugzilla.
The link is clearly something that needs to be configured for most WMF wikis. It'd be a lot easier for the devs and the users if this was simply an interface message so that admins could easily change this without having to go through bugzilla.
Note that ULS provides a similar message at Mediawiki:uls-ime-helppage
See Also:
T58036: "More info" link on Special:Notifications has broken localisation