Not Boost specific, but hopefully that's OK. I'm wondering whether Lemmy content is subject to crawling by search engines like Reddit is. Especially for certain topics, it can be really handy to have and occasionally a good way to discover a community.
Might depend in the Server, I guess. Try typing into your search engine a request like "site:lemmy.ml" or "site:lemmy.world" to see if it gets any results
Ah yes, it does seem to pull results, though as another person mentioned it probably won't be a major source due to poor seo and obviously far less volume/activity compared with reddit.