Linux on the desktop would have succeeded with a stable driver API. Having hardware with closed source drivers supported could have being a walk in the park for OEMs. Bad 3D, wireless, etc. support is what killed Linux. OEMs would have probably made more and better drivers if they didn't have to make changes to them every few months or go through the effort of releasing and mainlining the source.
That chart with the growth of the Linux kernel discredits everything. The Linux kernel continues to grow because they are obsessed with keeping all drivers in mainline instead of having a stable API for them as any sane project would.
(Eastern) Europe has also experienced what happens when communists are in charge, yet communists are not being persecuted in any way, while fascists or nazis are. Something else is going on. Case in point: this comment is being downvoted without any explanation.
If you read TFA, you'll see you can get the .app file from the App Store and then turn it into an ISO with a script that's included. But you can also use your favourite torrent site, like The Pirate Bay, to get an ISO.