And then that'll leave a market for someone else to come along and serve.
If the company that owns the distribution rights to a piece of content doesn't want to support the last few percent of the market then they just won't and there's nothing anyone else can (legally) do about it unless they start further up the food chain, making their own content. And if there were enough money in those outliers for that to be profitable, then the existing content creators would probably be serving them.
DRM is going to happen one way or another, and in my mind ensuring that at the very least the DRM itself has a defined interface for everyone to work against results in a more "open" ecosystem than leaving it up to backroom deals between content creators and DRM vendors who create hacky hodge-podge software.
The people this hurts aren't going to be the media companies or the normal users. The people it will hurt will be us crazies that do stuff like run Unix on the desktop or try and run unlocked Chinese Android phones, because they just won't be supported because there's no financial case for it.