The author forgets to mention that buying AMC might be interpreted as declaring war on other content producers. Sure Netflix has dabbled a bit in funding productions, but starting to slice into another pie will just make their core business model more difficult to maintain if misinterpreted.
This is probably not a big concern anymore. Almost all the major studios are in bed with a distributor of some kind. HBO & Time Warner, NBC/Universal and Comcast, and so on. Disney is the only one I can think of without some cable arm attached, maybe Viacom? Fox has/had Sky internationally and used to own a piece of DirecTV, IIRC.
Thus, Netflix wouldn't be an outlier, but part of a broad change/consolidation happening to the industry.