I just saw, that fedidb now has data for the biggest fediverse accounts, so I did a little plotting with it. Here is a graphic of the scattering of the 100 biggest accounts by the instance they are on. 38 of them are on mastodon.social https://fedidb.org/popular-fediverse-accounts (the data is in the alt text) #mastodon #chart #fedidb #fediverse
And a lot younger - the project is less ready for prime time than Lemmy is. I think the last thing kbin.social needs right now is more users.
As a software Kbin is also more fragmented - most kbin users outside of kbin.social are running mbin.