You know, I'm a bit late to the discussion here (though I have followed this game for ages), but it does seem to me like he may just be feeling inadequate to keep up with the insane scope of the project, and that he lurks because he doesn't know how to relay this to people who have supported him.
Speaking from an empathetic perspective, I know I would feel utterly embarrassed to let down people who have supported me for ages, and honestly would keep lurking just to see what people are saying. The best remedy to this would be to inundate whatever servers he is on with positive vibes and messages like what you said Malakai, "Game is great!... Cant even remember how many times i played thru..." etc etc, to give him a consolation boost and let him know he still has support regardless of his radio silence, and that his game is still hands down one of the best in the business. Can you imagine receiving hundreds of only positive messages in the span of a few days? I personally get such a boost from words of affirmation, maybe that would give him a little courage, if not at least boost his own self-worth.
To that end, I would like to do that too, but I don't even know how to reach out. Where is he lurking exactly? Is there a non-expired invite to said servers where he is active? Because I've struck out on Discord... (EDIT: scratch this, finally managed to get the invite link to work by copying it over into the app on my phone!)
Let's all band together and let legacyuser know what a legend he is and how much we appreciate everything he has done already!