what stops someone from using a sock puppet account to upvote their own content and get in the rewards every week?

unless i missed something (the source link goes to a 404?) it's closed source?

assuming that is just a mistake, the model is not censorship resistant at all. it's a centralized server. I assume the website can prevent you from posting, logging in, or can just take the whole site down if it likes.

but since it is a topic-based forum and not a follow-based social platform like X, Facebook, Insta, or most of nostr, running a centralized server isn't really a big deal.

forums aren't really designed to create a social graph like Twitter, they're just about the topics. So, if you are worried that the website operators will censor you right-click save the stuff that you find interesting and copy the code (when they make it available) so you can spin up your own version when they try to censor you.

have you thought much about why the sybil fee is (was in your case) important?