Basically for me the fewer working on the project, the less motivation i have to work on it. We haven't really "officially" stopped development, we have just become busy with other stuff college, various other game development projects, etc.
There is still the rewrite code that i also occasionally work on which is still very very early: https://github.com/mdsitton/fofix-rewrite
And regarding Phase Shift it looks like the project has suffered from some similar problems that FoFiX has gone through. The code apparently from some posts I've seen on their forums is in pretty bad shape for example here is a post i have quoted about the subject.
This is something I have considered for a while but there are a few reasons why I don't think it would help much.
The first is that my code isn't that well notated. Even I often don't know how some of it works and I always have to spend 5-10 minutes figuring out what the code does. So if I was to release the code or have someone else help me I would feel I'd have to always be on hand to constantly explain the code and as such I might as well just write it myself.
Secondly, this was my first coding project and I literally was still reading my C++ for dummies book during the first few months of development. As such there is a load of old code that is quite embarrassing and that still plagues a lot of the game. Instead of fixing this code I've just learnt to live with it and that's just created more bad code. So if I was to release it I'd want to fix all that up beforehand which takes time.
There are a few other reasons that relating to online play and hacking etc. but they can all be overcome in some form or another.
All that said I would really like to work with other programmers. Everything I've done so far has been pretty much solitary. I'm sure I could learn a lot from working with people more experience than myself and if the right thing came up I would like to do that. However, I think I would get more from just starting a new team project rather than having to live with my old code as a constant reminder of how not to do things.
The main reason FoFiX has seemed so dead is because we opted to do a huge rewrite of a lot of the code. The major parts remaining are huge tasks. There are also some release breaking bugs that have resulted from those rewrites.
With phase shift they seemed to have opted to keep the bad code around so over there they can still fix bugs and have maintenance releases which makes the project seem somewhat more alive. The current FoFiX current code has diverged/improved so much since the last release that it is hard to even touch the old code. Especially for me since i came to the party after 3.121 was released and well into the development of 4.0.
Also another large demotivational thing for me is that i have learned so much more about python, programming, and OpenGL since starting some other projects, that sometimes it can be painful (even after these rewrites) looking at the code...
Which I hope to in the future take what I'm working on now and use it to actually create an improved FoFiX/music/rhythm game. repo: https://github.com/explosiveduck/cubix