It's too late to do anything about it now but I wonder if it would've been more effective if all the participating subs agreed on a common time (i.e. 12:00AM UTC or whatever) to go dark rather than leave it up to each subreddit.
The only disadvantage of this is that I’ll need to wait two days so I can continue transferring my whisky reviews to the Whiskybase. Them being on Reddit is the only reason why my account is still there.