Sorry, but that is utter bullshit.
Somehow Stallman's importance is somewhere in foggy future with a lot of handwaving and FUD.
The real relevance of his ideas is already in the past.
I won't be surprised a bit if at the time you are talking about most OSS will be under MIT/BSD type licenses not GPL.
Strong disagree. GPL licensed software is powering an ever increasing fraction of all devices. Far more than I would have ever believed in only a decade ago.
There are some interesting network effects at work here. Th e more GPL'd software there is out there the bigger the chunk you have to write yourself (or pay someone to write) would have to be if you want to forego it.
Hence Linksys and Android.
Those would have never gotten as far as they did without the GPL's software underneath their externally visible features as a foundation to build on.
Linux on the desktop may never happen, but linux in your pocket is pretty much a foregone conclusion at this point.
Android is an interesting example. Google did use a linux kernel but threw out everything GPL they possibly could above that, to the point of writing their own libc. So I wouldn't really call it an example of GPL winning. It's equally an example of how it was necessary to throw away piles of code because it was GPL's and couldn't be used in commercially compatible way.