Maybe Google isn't crawling all the pages on the site? Possibly related to being an SPA?
Otherwise, I think this is a pretty cool project. I've always thought that Slack and Discord communities lack a good way to find them.
https://www.google.com/search?q=seeing+a+weird+issue+with+fl...
We built Linen on Nextjs since I wanted to server render all the content so it performs better for crawlers. But getting Google to crawl a large number of pages is tricky. It takes a while and even with a submitted sitemap Google sure takes their time.
Depending on the community after a month or two you end up seeing a few hundred pages being index by Google. Their ranking will vary based on how relevant the content is or based on some Google magic. Since I render the content that is newest on Linen it probably won't be on Google for a while.