It seems Kojima wanted to place the hands of his creation towards artists he is familiar with, but things just didn’t snap into place. Apparently, letting go is easy. But getting someone to carry on the legacy is too difficult. According to Kojima from an IGN interview post-launch:
I’ve been trying to pass on the baton to my younger staff to create the series, but it was difficult, and I kind of look back and think that maybe this was the reason that it was difficult to say to the younger creators that they should keep on creating Metal Gear. For instance, motion capture – some other teams might have different units to do motion capture sessions. Some might have a totally different unit to write the motion capture script, maybe they might ask Hollywood to participate and things like that. But for Metal Gear Solid 4, I was doing all of this together, so it was easier for me to do it because I could think of the game design and which emotion would work best and things like that.
Hang in there Kojima. We know you want to.