I know that's probably rhetorical, but probably a similar problem to modern movies where (as described in the video Why Modern Movies Suck - They're Too Expensive) they are going after spectacle (rather than story or other elements) and due to cost they must make a 'safe' product to stay profitable, where a bland but universally palatable product will sell more tickets/copies than a stellar niche thing.

I'd also add that companies know they can usually ride the success of their own name/brand recognition. Even worse here with games because of pre-ordering, early-access as a product, and crowd-funding (which some wildly successful publishers still do--on top of unpaid self-promotion and all the other things--because people still think of them as indie).