Hi. Sorry for not posting in this thread for a while.
I'm one of the "official" maintainers of SBEMU on GitHub, although crazii is the creator and was the primary maintainer. But indeed he seems to have taken a leave of absence from the project. He's done so before, only to return after awhile, but this time he's been gone from the project for a lot longer.
I've been wanting to look into picking up further development of SBEMU. But I haven't gotten around to making time for that.
I've been mostly involved with CI/CD automation and some testing of SBEMU, and not as much with the code base of the project itself.
One challenge w.r.t. further maintaining SBEMU is the fact that it relies on an (apparently unmaintained) forked version of HDPMI, as opposed to the upstream version of HDPMI created (and continuously maintained) by Baron-von-Riedesel, the same guy who created and maintains VSBHDA.
If I understand the interactions between crazii and Baron-von-Riedesel correctly, this HDPMI fork happened due to a certain technical disagreement between the two. VSBHDA may have been created in part due to that same difference in philosophies and technical approaches. (Someone here please correct me if I'm wrong about that, though!)
Although SBEMU precedes VSBHDA (it started about a month and a half earlier, if the Git commits are anything to go by), the former indeed appears unmaintained, whereas VSBHDA is seeing continued maintenance and development on both the tool itself and on its dependencies (unforked HDPMI, Jemm and QPIEMU.DLL).
SBEMU remains, at least to my knowledge, the first DOS Sound Blaster emulator that solved the protected mode compatibility problem, and for that, we owe crazii an enormous debt of gratitude. (Again, if someone here can point out an older such project that worked with both real mode and protected mode games, feel free to correct me. But I had been looking long and hard for one before cazii shared SBEMU with the world.)
One advantage that SBEMU has is that supports a wider range of target sound devices, whereas VSBHDA sticks to the most popular ones. But it recently also got MIDI emulation (thanks to Cacodemon345 here on VOGONS who initally forked VSBHDA to VSBHDASF and had it merged back upstream).
But I think we can indeed more and more conclude that SBEMU, as much of a pioneer it was, has become unmaintained and VSBHDA seems to be the way forward. In my experience, Baron-von-Riedesel is quite responsive here and on GitHub and is very active w.r.t. working on the various cool projects he maintains.
I'm not ready to mark the SBEMU project as abandoned yet though, since crazii might pop up again to resume work on it. As I said, this is not the first time he's been absent for a longer period of time, only to come back on the radar a while later. I wish him the best, regardless! (I'm assuming he's a "he", based on his GitHub avatar.)