Wow, that's some bad usability there. Talk about chasing the shiny over form and function. Javascript pages are the 'Flash site' of the 2010s and I can't wait until it's similarly consigned to its rightful place in the dustbin of history. All they do is waste my CPU time and memory, force me to enable a scripting language that is riddled with vulnerabilities just to see some content, and run more slowly than real pag…
Why is the usability bad? Pages are pleasant to read in that aspect ratio and it seems to provide a good solution to what to do with the bits around the edges. I like the stack of places that I've been before as context and think that it encourages exploration and clicking around more than the original site.
Also, simplicity of core architecture leads to diversity of tools. If Google's first crawler had to execute JavaScript and make sense of single page applications, Google wouldn't exist today. So be careful when you encourage websites to become more complicated.
Tim Bray said it well in 2003: "Browsers are more usable because they're less flexible." https://www.tbray.org/ongoing/When/200x/2003/07/12/WebsThePl...