Edit: as someone who grew up in the 80s, Linux is the best thing that happened to computing outside the internet and Linux was a large part of that as well. It was hell before with MS, Sun, HP, SGI, Digital, etc and their flavours of hell. They did a lot of good but the closed off nature was terrible.
Myself, I run a small ARM box running (an embedded and completely inaccessible) Linux, designed as a dedicated streaming device (or sometimes a similar device that is included in the workings of my Blu-Ray player). I'm not particularly interested in using a TV as a display for a general-purpose computing device, so this works well for what I want to do.
I have a few ARM boxes that can't play anything DRMed other than what's handled by libdvdcss or libaacs, but those are the devices that I wouldn't use to play video even if I could.
How? Do you really watch video in the browser on your computer where you can run Google-provided builds of Chrome? Isn't that pretty annoying?
What do you do if you have some random small ARM or Atom box running Linux with an UI that's convenient to use on the big TV screen it's connected to and using a remote control? I don't see an obvious way to watch DRM-protected video there. HTML5/EME doesn't help a bit as you still need a (binary-only) content decryption module that you can't get for your platform.