Meta announced that users on Threads will be able to see fediverse replies on other posts besides their own. In addition, posts that originated through the Threads API, like those created via third-party apps and scheduling services, will now be syndicated to the fediverse.
The owner of kbin.social (and creator of kbin incidentally) has been MIA for a few months now, so it’s presumed that it’s over. I haven’t heard of anything concrete regarding the fate of kbin.social or ernest though - unless someone has heard differently, it remains possible that ernest returns in a year or two and brings kbin.social back up.
Edit: I thought that https://kbin.earth/ still existed as an instance still running ernest’s original flavour of kbin (as opposed to its sucessor mbin) but it turns out it has been moved to mbin as per the reply below.
With that, I’m not sure if anyone is still on the original kbin codebase at this point.
This is not true, as of 4 months ago. kbin.earth is running Mbin now.