According to Reddark [1], there are 5 subreddits with over 30 million users each which will go dark next week:
aww
gaming
music
pics
todayilearned
Considering how easy it is to run a forum, one would think there must be
some alternatives out there on the web?
If find it pretty hard to find those though. Does the HN crowd know some alternatives?
[1]: https://reddark.untone.uk/
Making a statement online isn't typically terribly effective at causing change.