As part of the devs farewell message on their site, they have included malicious code to make each visitor sends 2,000 requests to the dbzer0 servers in an attempt to DDOS and take the instance offline.
I think it's the pressure and the solo developer model
You put something out. It seems to be running. There are bugs. You fix them. There are more bugs (pareto is a PITA). You fix them too. Someone accuses you of sacrificing kittens in the basement. There are ideas for features and more bugs. Some worded in an entitled or just tone-deaf way. Very often you're the only one working on the project and saying "I accept PRs" somehow became received as a FU. It becomes hard to put the project away for just a week
You are perpetually in "I-fix-it" mode
Not to mention that in order to even start a project like that one needs to have at least a bit of "fuck it, I'll do it myself" mentality
It's a pity that !unfinishedprojects@forum.unfinishedprojects.net wound down. I hoped it might have been a space for projects to find communities. As we see around, it doesn't require a 10 person team with a kanban board to write something that works. But on the other side of the spectrum I think a project needs some sort of community around it. So even if there's only one dev, someone else could write the tutorials, less technical parts of docs, help new deployments etc