I would shift the blame back to Reddit here, because they exposed data to mods that are completely unrelated to the subreddit. Another problem is the non-existing appeal process.
"participation" can take multiple forms. As far as I remember, I actually challenged some of the more egregious posts I saw on /r/chodi, but didn't spend too much time there, as who has the time to educate the whole planet?
If that other sub is so bad, then Reddit should ban it outright; why recommend it to users only to get them banned in other subs?
Anyone can build a bot that automatically watches any submissions to any subreddit, and bans those users from their subreddit. Like it or hate it, reddit is very hands-off with how subreddits are moderated beyond maintaining overall site rules.
Using a VPN and alt accounts are practically a necessity. I have 3 main accounts: one only posts on niche hobby forums, one for "clean" subreddits (/r/news, pics and the like), and one for anything remotely controversial.
Similar here. I differentiate by how little I care about revealing my actual identity and location. Like for hobbies and stuff I really don’t care if people know my approximate location. But for some stuff… dudes are crazy. Would rather not get doxxed.
this would have the effect of making everyone's activity private to everyone except for scrapers (the actual bad people nobody wants to see their activity). Not sure how this would increase privacy at all. Activity on reddit outside of private subreddits is known to be public
There is no technological solution to most social problems, and you can hardly expect Reddit to mediate social problems like ban appeals at scale (I mean, you can, but it won't happen for $ reasons).
Most of the big subreddits are co-opted by toxic, power-mad moderators, or completely devoid of moderation entirely. A complete purge & reset wouldn't be a bad idea.
GP mentioned that he "commented a couple of times", which means that his participation in the other subreddit is public knowledge.