He's damn right to stop development on a game he doesn't want to work on, his main aim is to make fun games, he’s proven he can do this once with Minecraft so why not let him go back to what he likes and see what he comes up with?
He recently took part in 7DFPS a 7 day competition in which you’re set the task of building a First Person Shooter (FPS), the result of his 7 days of work? Shambles. I’ve spent a while playing this game and it's a ton of fun, check it out. I think it’s a perfect example of what Notch wants to do, and explains his ambitions as a games developer better than any blog post.
Going back to 0x10c, I think it’s great that the community has come together and begun development of a “spiritual successor” to 0x10c. Whether they succeed or not doesn't mater, what's really interesting is that they took on this task. I'm not sure how practical it would be if the game's code and assets were open sourced. His work won't go unwasted though, Notch has helped start, what I think is one of the most interesting collaborations in the gaming industry.
"I want to do smaller games that can fail," he claims, adding "I want to experiment and develop and think and tinker and tweak" This is the kind of developer Notch is, so let's see where this goes! He might accomplish nothing, or he just might find the new big thing in gaming. Only time will tell.