Finding a camera system that works for you is all that matters, people who bang one about this is better than that because this and that... whatever. You show those people an image from a Phase 100Mpx back and they just comment some excuse as to why it doesn't count. It's all a bit of fun down the pub [or on the internet/camera club where it much more heated it seems] but out in the real world, as in doing it for clients, all that matters is you exceed their expectations and deliver what was discussed. What system you do that with is up to you. Full frame is better and so is APS-C and so is Medium Format and so is a mobile Phone...
This is that shot of Dwayne Johnson by supremo photog Michael J. LeBrecht II for the cover of Sports Illustrated that was shot on a Mobile phone - looks mighty fine to me.
forum: Camera Vs. Camera
Some people can do that without a camera, any camera at all, by literally painting it all in a photoshop.
How much photoshop is in this picture? I think plenty. Maybe even too much to call it a photograph