You can cache some REST requests which would reduce the load of serving them out of the web socket request each time.

More importantly though (with either of these) is that when Google looks at the page, there are no links for it to traverse or index.

This also means that the site/community isn't discoverable from a random person searching for it inhibiting organic growth.

For example, if you do https://www.google.com/search?rls=en&q=where+to+discuss+star... it will likely never return a link to Lemmy (it may return pages that link to lemmy - like the reddit page), but not lemmy itself.

Choosing a random Lemmy instance, I see server rendered content and <a href> links that are followable. Searching for 'site:<instance domain>' on Google turns up plenty of results, very much identical to what I see when searching for 'site:reddit.com'. Google seems to have no trouble indexing the site.

I expect you won't see results on Google, save for when you explicitly ask for the site, because there isn't much in the way of reputation. You are highly unlikely to see my personal blog, which is just plain old boring as it gets HTML, come up in search results for the same reason.