Back in 2016 I did a similar approach to calculate related users: one using graph similarity (https://minimaxir.com/2016/05/reddit-graph/ https://minimaxir.com/

Back in 2016 I did a similar approach to calculate related users: one using graph similarity (https://minimaxir.com/2016/05/reddit-graph/ https://minimaxir.com/2016/05/reddit-graph/ , albeit the embeds broke) and another using jaccard similarity (like this viz) with a different approach to visualization which IMO turned out easier to interpret than a graph-based approach (https://minimaxir.com/2016/06/reddit-related-subreddits/ https://minimaxir.com/2016/06/reddit-related-subreddits/ )