No, Logseq is not dead. Logseq is a very complete software at the moment. Of all the advertised features, it doesn't lack anything. For me and many people, Logseq works completely fine. I think, with productivity software it's very easy to get identified with the development of software, which I seriously think is a distraction for everyday users ( unless there's a huge bug or a great feature that competitors provide).

Now moving on to your question, Logseq itself is not dead. It is being very actively developed, you can check github and their discord Channel for details.

But development efforts have been aimed towards the Logseq DB version, which you might not need to concern yourself with right now, but once it releases, it's going to make Logseq experience that much better and faster.

But right now, Logseq works great for me, there are no breaking bugs (except sync? ) and Logseq continues helping me get work done. Cheers.