On a contextual basis, sure there are differences where smaller more independent producers are picked up by the Big Three - but unless they're contractually bound to not offer it on any other platform (in which case it is a different can of worms) I can't see any reason that putting it on multiple platforms would hurt their exposure.
Wholeheartedly agree with you here, but there're a couple additional reasons that this happens.
The biggest costs are licensing with the big three at all. One - it's pretty costly even doing it, and Two - you want to make sure you get a good return on it.
(The game I'm contributing a design for, Kaiju Combat is releasing on PC-only for now, because it's a KickStarted Project and initially attempting a console release is WAY outside what our budget is, and we want to make sure that if/when it's done that there's enough exposure to at least make up the cost of doing it).
On top of that, with the PS3/360, the development architecture was REALLY different, which would have been a cost all in its own, but from what I know about the XboxOne & OS4, they're MUCH more similar comparatively speaking, and that should make everything lots easier for the Indy Devs.
Overall, everything about this generation seems better for the smaller Devs.
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