I think much of it also just comes down to how hard sony works to help indie developers.
http://www.venomquest.com/2015/05/14/no-mans-sky-could-get-a-blu-ray-release-teases-playstation-uk-boss/
“No Man’s Sky has been treated as if it was from one our internal studios. We’ve been working very closely with the developers and bringing it into our release programme as if we had made it. We are not going to treat it any differently and we are going to put the full weight of PlayStation behind it. If it all comes together as well as expected, it will be treated like a first-party released; it is not a self-published small indie title on the platform.” - Fergal Gara
I think its fair to say sony puts in more work, when it comes to helping indie developers than MS does.
