Review boards that should be maintained by volunteers, are they active? If not, just redirect to mw.org. If community doesn't want centralisation, make it very obvious that the page is no longer watched by WMF staff (maybe also update my user page there to help explain that). For certain communities with a particular visual editor configuration, a different engagement model may be offered.)
Not centralized boards:
Not centralized, but with explicit community commitment:
Q: What can a community member do when centralization seems impractical?
A: Volunteers who watch feedback pages simply help with requests as they come by: they look up on Phab if those are already known, otherwise they file a new task, because Phab is how you put things in front of devs' eyes. For cases that look urgent, they ping Community Liaisons for a second opinion or action. There are several useful links for them linked in the box at the right of https://www.mediawiki.org/wiki/VisualEditor/Feedback .