So many ways to look at it...
On the one hand, if you're a software developer chances are is that once you reach a senior position, you'll be likely being working in a more administrative role, much less hands-on. That turns some off, Yuji Naka is probably one of those.
I haven't looked much into what Prope has been doing, but not much apparentely since their latest update was all the way back in April 2017.
The other way look at it, it's the completely random nature of it. Working for SquareEnix on some big RPG maybe? I mean he did work on Phantasy Star...