The only key developer that went to BSDi was Mike Karels, and he didn't go until a year or so after BSDi was founded. Mike left before Kirk and I did because he wanted to return to Minnesota to live, and the fact that BSDi needed a system architect made it a natural and easy move for him. Kirk and I stayed at UC Berkeley for a couple years after that, then I took a year off and spent a couple of years at BSDi. Kirk has never been a BSDi employee, although he's consulted for them and is now chairman of their board. The bottom line is that, had there been continued funding at UC Berkeley, we would all have stayed there, probably forever.
Universities are really, really, nice places to work.
But, all of us were engineers, and none of us had any interest in spending our time fund-raising, and the University no longer had any real interest in keeping us there. So, we looked around for some way to continue doing what we liked to do. And we wanted BSD to continue to move forward. But that was an engineering goal, not a money-making one. Especially after the OSF group was created.