Trash them and replace them.
Everything you said here is 100% true. However, it really doesn't work like that, where another dev could just step in. There are a few examples where the dev of a VN either dies or gives up and passed his game to someone else, and it never works. The new person is just never as invested in the original game to do much with it. Look at Lexi or Oath of Loyalty as an example. I can't think of a single case where the primary dev (or pretend dev in Bluecat's case), gave his game to someone else and it continued without being quickly abandoned.
If Bluecat himself is not invested more then making the occasional snarky comment about how normal time doesn't apply to cats, there is no way some replacement dev will care either. They will be happy to collect the 1000s a month Bluecat is still getting (unbelievably to me), but they won't continue with the story either. It will just be a different person keeping silent for 2.5 months at a time, and making BS excuses why a non-rendering, non-branching, stock Renpy interface, no real story game like ES is too complicated to release.
It's not like Ecchi Sensei is unique among games here, so another dev would be driven to continue because it is one of a kind. How many school-based games with mostly Asian characters are there? I can think of at least 10 off the top of my head.
Any competent dev would want to avoid this shit-show and use his time to make his own game.