My understanding of this argument, as best as I'm able to state it, is approximately: Claims that view-source is a significant virtue of the web are nostalgic and misguided, as demonstrated by the fact that it's difficult and rare today to find anything usable or valuable by reading the javascript source of major websites like facebook, especially by amateurs.
It's possible that I've misunderstood some nuances about the claim, and I apologize if I've misrepresented the comment you're replying to.
Sure large sites with extraordinarily valuable IP make it hard to view source and learn anything. However other smaller sites are a wealth of wisdom. Just the other day for example I inspected the new KIKK website to see how they managed to keep their website silky smooth on mobile whilst cramming quite a few transitions/animations in.
And for that matter I learned a heap inspecting (whilst attempting to reverse) Google's culture project. Specifically how they protected their image assets using a novel technique (since this was in pre-web-DRM world).
The other thing is as sites know their code is in the open I suspect it's easier for devs to get internal approval to do write ups of particular techniques.
The discussion was about why the web became a successful platform in the first place. There is no doubt "view-source" was a very significant factor in this. This is basically how the first generation of web devs learned the craft.
It's possible that I've misunderstood some nuances about the claim, and I apologize if I've misrepresented the comment you're replying to.