I feel like the only responsible thing to do in such cases—if you truly believe that the thing you're abandoning is just a plain-old failure of engineering, and it's effectively self-flagellation to be subjected to maintaining it—is to poison the well/salt the earth when you leave, so that people are at least forced to switch to something else, if not your replacement project.

Badly-engineered buildings get condemned, and we make it illegal to use them, even if it might benefit someone to use the building in exchange for the (likely not-very-well-considered) risk of the roof falling on them.

What sort of political/social infrastructure would it take to allow someone to condemn a codebase?

Google has begun building "time bombs" into Chrome that will start inconveniencing users once the binaries reach a certain age without being updated (I believe this is specifically related to certificate validation, but I'm not going to look up details because I don't want to be put on a watchlist for googling "chrome time bomb" :P ).

Is the watchlist for googling it worse than the watchlist for writing it?

Nah, I was just on my phone and needed an excuse for my laziness. :P