Here are a few I've discovered that I've really been enjoying lately:
https://tildeverse.org (EDIT: apparently they don't like being linked to from HN; copy and paste the link instead of clicking it)
I think the main focus of those communities is recapturing the spirit of the (arguably more fun) internet of the 90s to early 2000s. They're not specifically dedicated to static site minimalism, but there's definitely a large overlap.
