Recently I noticed that I often have some add-on config warnings in my system log, such as this one:
WARNING (MainThread) [supervisor.addons.validate] Unknown options web
Which means that the config variable web is no longer valid somewhere in an add-on and should be removed. The only question is with which add-on?
As part of the Usability Heuristics, where the above actually breaks rule #9: Help users recognize, diagnose, and recover from errors. I would suggest that this type of system warning indicate which add-on is involved.
The next step could be a notification to the add-on page itself that indicates that parts of the add-on config are outdated and that you have to remove it.
I have already discussed this with @frenck before, would say let your opinion speak and vote!