I'm the author. Thanks for pointing this out.
I completely agree with your premise. JavaScript and the browser represent the quintessential modern authoring platform.
I actually wanted to write more about JavaScript, but the problem was that there were fewer cohesive, codified sources to cite than I expected. When writing about this kind of historical narrative, the first issue is always whether there are books you can cite.
JS has undergone organic changes along with the turbulent history of the web itself, but there's no clearly organized history of those changes.(To be more precise, it's not that there are none, but rather that the web environment was so fragmented in its early days, and each piece had its own history. Describing all of it would have required too much time)
There is Allen Wirfs-Brock and Brendan Eich's 'JavaScript: The First 20 Years,' but it's so lengthy that I couldn't read all of it, so I had to cite only what I had actually read. That's why I ended up cutting a lot of the JS content. I completely agree with your point, but I hope you understand it was a matter of length constraints.
To me, what makes this so obvious with the web platform is the bureacratic nature of developing for it. To do anything meaningful, you have to bring three departments together (html, css, and javascript). Each is a very different language designed for a different guild of practitioners. You even have the interdepartment turf wars, even if one single person is manning all 3 departments, of which department should accomplish any given task. And each department/platform/language has exteded their capabilities over time to give them more reach to participate in problem solving formerly left to others.
Thanks for your paper btw. I did 20 years of Smalltalk. I came to view Smalltalk programming more like biological culture manipulation (you had a dish of live objects that you morphed into the result you wanted), whereas the conventional file->syntax->executable employed by most development systems is more akin to the industrial factory pipeline of assembling products from raw goods.
During those younger years, money mattered. Tools were sold on the premise that they reduced or mitigated the various costs inherint with employing programmers. And then... around the late 90s, that just kind of dropped from the discussion. As quantitave easing made money available to speculate with and hitting it big with the software that was "eating the world", things like web programming burgeoned with very little thought about "does this make it cheaper".
The web is merely a small interface substrate. Spread wide sure, but the bulk of the work is shouldered by the backend. I think if there’s a true winner of the web era, it is languages like Java, C#, Ruby, PHP, and Python. There are many codebases tied to those more than they are tied to the UI written in JavaScript.
That's like saying the bulk of all writing ever printed to page was shouldered by the ink (or what about the felled trees; maybe the logging company?). It completely misses the point.