I agree that showing a "hey this is broken" warning is better than rendering a totally broken page, but it's still not as good as presenting at least a partially working version, perhaps minus all of the usual bells and whistles. Now, of course, this is not super-feasible if you've chosen to build most of your site using client-side code, especially if that's where most of the rendering happens. But then again, the lack of server-side rendering is the obvious downside of building your site that way.
My position is that if you disable Javascript you get what you get (both you and I will be happy to know that I don't do web development anymore).
The point for me is that links behave like links (perform GET requests against a URL and change the page from one state to another), buttons behave like buttons (perform POST requests and update some internal state), and the effect they have on the page is much the same with or without Javascript. The only difference is that with Javascript I can intercept the action and make the state change a lot more streamlined, or add a fancy animation if I so desire.
By simply intercepting buttons and links (similar to how pjax and turbolinks work) I don't have to dig through JS to find where a specific AJAX request is fired-off and what it does. It just works, and when it returns, it simply updates part or all of the page with whatever the server returned, which could be part or all of a page.
There are, of course, obvious limitations, like local state that changes with user interaction but that isn't preserved on the server in any way. But the more I can get working without Javascript, the more I know will be easily maintainable and translatable going forward even if I do something crazy like get rid of jQuery or convert everything to a React app.
Maybe I'm just a bit odd, but I find this approach a lot easier to manage and a lot more productive in the long run than in marrying myself to any particular client-side framework.
(I have my doubts one in fifty people disable Javascript)
The react-rails gem is capable of doing server-side rendering out of the box: https://github.com/reactjs/react-rails
But I do have apps I maintain that started as traditional Rails apps and have been progressively enhanced to a point where they perform a lot like more modern client-side apps. And an interesting property I've discovered to be true of such an app is that it's really quite easy to convert that traditional view-rendering pipeline to React, because there is almost no JS-soup being relied on for core pieces to function.
On the flip side, I also work on a couple apps where most of the functionality exists as JQuery DOM manipulation or as Bootstrapified data binding, and these are nearly impossible to port to a diff-based rendering library like React without rewriting most of the functionality.
So while I haven't exactly tried rendering React on the server, I've found that the more traditional server-side rendering flow still holds up quite well on the modern web. It's a good way of thinking about how your app should look/behave given a set of states, and it holds up well even in places where Javascript is required. The fact that it can be accomplished without Javascript is more of a side-effect, but also a good indication that it's not any particular bit of Javascript that is holding it all together.
Admittedly, they did not look as good as sites do today.
The part I might be wrong about is "doing progressive enhancement really well is much more expensive" - that's just my opinion based on anecdotal experience.
[1] Some examples of sites that won't display anything if Javascript is disabled (even though they're most displaying text): http://googlecommerce.blogspot.co.uk/ http://googleandyourbusiness.blogspot.co.uk/
1) MAJOR parts of our app will not and can not work without JS. Period, exclamation point.
2) Because of point 1 it doesn't make sense to waste dev time on making some views work with/without JS (We are a younger company and don't have time to waste on something like this especially when it isn't public-facing, not to mention QA can't handle testing everything twice).
3) Even if V1 of a component does support both JS and no JS there is no guarantee that future updates will be able to keep feature-parity or have time to code for that.
For me JS is part of the web, not an optional add-on. It would be like saying "make a webpage that works with HTML" (IMHO).
I also feel that it's not fair to complain about the GOOGLE CHROME app store requiring GASP GOOGLE CHROME (Same for GOOGLE cloud print). Not shit sherlock. As for Apple not allowing their video feeds on anything but Safari+OS X I think this is BS, there is no good reason I can think of to alienate so many people on other OS's especially since I would think THOSE are the people you might want to reach with your keynotes to convince them why they should switch.
So while I like the idea of this Tumblr I can't help but think the JS/Google Chrome examples don't really fit and distract from the overall message. To be honest looking through the Tumblr again the ONLY valid concern is the one with Apple's keynote streaming, the other ones make complete sense. How is it Google's fault that they are pushing the envelope in terms of what is possible, even Google doesn't have the time/resources to make every one of their ideas (which may or may not make it long term) work across the board and that is their prerogative.
I read that as complaining about a WEB APP store requiring google chrome. Web apps tied to a specific browser are destructive to the overall ecosystem; you might as well just distribute native apps.
What I'm not a fan of is "Lowest-denominator web is the best web" arguement. It's not and I'm sorry but unlimited backwords-compatibility is a pipedream, at some point you have to move forward.
As for what requires JS: we use google maps and people need to be able to draw zones on the maps which is not possible without JS (unless we have them a bunch of text inputs that they could enter the lat/lon of all the vertices. That is just one example and I can't go into much more detail. Bottom line is we would not have the customers we do if we didn't use to make it faster/easier and we don't have to resources to support JS+Noscript/no JS.
This does appear to be the case with the first warning published on the blog, where the site is put into a "read-only mode" and I disagree with it being listed there, but I come across many other sites which do not display any form of content at all when JavaScript is disabled.