

The web interface can already be reloaded at any time and has to do all of this. You seem to be missing we’re talking about degradation here, remember the definition of the word, it means it isn’t as good as when JS is enabled. The point is it should still work somehow.
You don’t, I’m saying it would still mostly work. Getting messages as they arrive is nice but not necessary. For example, I personally have all notifications off, and I only see messages when I specifically look for them, no one can reach me instantly. Everyone seems to be missing that we’re talking about degradation here, it degrades, it gets worse with JS disabled. But it shouldn’t straight up not work.
A good example for something that does not work without JS would have been a drawing application like they said, or games, there are plenty of things that literally do not work without JS, but messaging is not one of them. Instant messaging would be of course.