Paul Greengrass won't do fourth 'Bourne' film

I love Paul Greengrass' films, and I was looking forward to him helming another "Bourne" flick, but according to The Playlist, the filmmaker won't return to direct another Jason Bourne installment. Bummer.
The project is quite messy, apparently, as two scripts are circling around and nothing has been decided on yet. George Nolfi wrote one, and Joshua Zetumer wrote another one, but no one consulted Greengrass.
The Playlist also points out that Greengrass' upcoming action flick "Green Zone" cost way much more money Universal wanted to spend. This could be another reason for his departure. He's too expensive.

Franck Tabouring