> If GNU/Linux were to die
But there is no such entity as GNU/Linux. It's hundreds and hundreds of independently working engineers who would all have to be hit by buses at the same time.
10 companies are responsible for 57% of the changes to Linux. This is better than the typical 1 company responsible for the majority of changes in a browser, but it's not remotely close to "hundreds and hundreds of independently working engineers". Volunteers only make up ~8% of the changes.
What we don't have is any browser that's a multi-company project, though. WebKit used to almost be that, but then the blink fork happened. The closest currently would I suppose be Chromium as it's also backed by Opera.
I think we're in agreement that Linux is in a better state than the browser. To nit-pick at your argument, Linux development is driven by people who are interested in working on it; many of those are lucky enough to have employers who encourage them to use a company email address to submit changes, and part of their working hours. Nothing indicates they wouldn't still be contributing without the @intel.com attached to their name.
Furthermore in the study you are referencing, the "8% volunteers" is larger than any company's contribution besides Intel and RedHat - even more if you add in the individual "consultants".
https://www.linuxfoundation.org/blog/the-top-10-developers-a...
If GNU/Linux were to die, so would all the distros, because it’s far too much work for any individual distro to maintain all that codebase. In much the same way, the intensive bit of maintenance work with Firefox is the rendering engine; there exist lots of “distros” (forks) of Firefox but they all rely on the same underlying codebase. It’s just not viable to have more than a small handful of rendering engines, much in the same way that there are only a very small handful of operating systems that can run on modern hardware.