When a developer is told to create a video game, the average mind will always drift to what has already been done. Given a blank canvas with which to work and the mind is assailed by the tyranny of possibility, creating nothing. The mind needs some structure and limitations to create, and often they are the limitations that creators impose on themselves. And often those self imposed limitations are the conventions of what has come before. It is a safety net that those steeped in a medium understand.
Conventionality in the arts leads to the exclusion of ideas that fall outside the norm, not by simply refusing to grant admittance to those outside the boundaries of what is accepted as a game, but through the subtle denial of new thought. Saying those limitations no longer apply in this instance is never enough. New limitations, specially crafted, are needed to break away from the old and into a new arena of possibility.