There are a lot of small, informal and fuzzy communities around specific interests in Twitter. For example, I routinely run into the same folks talking about some specific areas in PL/FP or in complex systems/resilience engineering. These sub-communities aren't clearly delineated like a subreddit, rather they arise organically through the same set of people following each other or, at least, consistently appearing in each others' feeds and conversations.
Japanese Bluesky isn't even close to Twitter yet. No politicians, no actors and actresses, no seiyuu, no utaite, a few mangaka and light novel authors, nobody that talks about trains, though there is the Frieren official account. There's a few Japanese that are just trying to generally meet new people or some that use Blueksy as a 1 way venting valve.
And as usual there are some political Japanese. In fact given how small Japanese Bluesky is the amount of politics is quite shocking given that Japanese tend not to be as vocal about politics on microblogging sites. (2ch on the other hand...)
But the en:ja ratio is like 5:1. Real population ratio between us:jp is like 3:1, and on Twitter it's more like 1.5:1 by active user count. This means Bluesky is less popular in Japan than it is in English speaking regions.
Our points are not mutually exclusive. Thanks for adding more insight. Is your bsky ratio based on actual users or the data at the link? (which is posts by language) Are there similar content stats for the site formerly known as Twitter?
Utaite. Will find barely any anywhere else. Thankfully if you're in one of those sub-communities, you don't ever get recommended anything political or American.
Discord is my goto choice for communities now, but I fear that company is not on a great trajectory either. It's like voting, you're picking for the least evil