Sorry, but that is simply not correct. You can implement a fully standard-compliant web browser by just implementing the ClearKey option. That has no patents associated with it.
It is likely a much better issue that H.264 is the dominant video standard used, and that requires paying licensing fees.
I was responding specifically to the point the GP post made about licensing fees.
What I meant was that there's no reason that there couldn't be a form of DRM that wouldn't require "licensing" in order to use it. It would indeed still have to be a closed-source binary blob—because, like you said, Netflix wouldn't accept anything less—but it could be a freely-redistributable closed-source blob, that any browser would be legally in the clear to include without seeking out a licensing arrangement.
Re: "it's not about patents"—while other IP laws (e.g. copyright) determine whether you have the right to just redistribute a copy of the DRM blob, patents determine whether you can reverse-engineer the original blob to make your own blob with the same ABI that embeds the same keying material, or whether that's also illegal. Patents, thus, are the ultimate difference between a blob you have to pay to license, and one you don't.
Why would anybody make closed source, freely distributable blob in the first place? Making zero money from it, but assuming responsibility for support (both client and server side) AND legal responsibility when hacked? Plus doing business development, in order to gain acceptance at all?
I've done some work on this last year -- it's possible to integrate with the Widevine PPAPI component (DRM library) included in Google Chrome to support decoding Netflix videos in any type of app.
Have you heard of this thing called Flash? Or Adobe Acrobat? Silverlight? MS Edge? Uber (the app, and incidentally actually/metaphorically Unicorn)? Google Maps? Netflix for iOS?
Flash is not free. Flash Player is. Flash is actually for-money product.
Adobe Acrobat is also for-money product. You probably meant Adobe Reader, which is similarly positioned to Acrobat like Flash Player to Flash.
Silverlight was and Edge is a way for Microsoft to prove value of the Windows platform, and in case of Silverlight, also of Microsoft developer tools.
Isn't Uber, the app, a way to sell services? Doesn't Netflix for iOS sell Netflix subscriptions?
Isn't Google Maps, together with all Google apps, a way to keep people online, use Google Search... and provide Google audience for ads?
Neither of these would be true for a free DRM. Just like Flash player was financed by selling Flash, Reader by selling Acrobat, Silverlight by selling Visual Studio, Edge by selling Windows, Uber and Netflix by selling services, Google apps by selling ads - what would you be selling in order to provide freely embeddable DRM binary? And tangent question, how would you build your brand?
As it stands, it is now legally impossible to create a fully standard-compliant web browser without paying licensing fees. That's a huge problem.