I've gotta wonder how often this happens in the general case: a prolific user and mod of large subreddits stops posting abruptly without notice. How many users are as active as maxwellhill was with similar seniority? Maybe a few thousand? In a given year, how many of them abandon Reddit suddenly? It seems like some scraping and basic analytics could yield an answer, and then we'd know the posterior.
Don't know if maxwellhill was ghislaine, but whoever he was, I think some big life event caused him to leave, and that it wasn't voluntary.