This is actually a well done web app in my opinion. You can disable javascript and the app loads just fine. JS is used as a progressive enhancement to hydrate.

This is actually a well done web app in my opinion. You can disable javascript and the app loads just fine. JS is used as a progressive enhancement to hydrate. Probably uses something like NextJS in the background. The HTML with inlined critical styles load in ~40ms on my internet. Sure it could be "better" in terms of TTI from the JS side but at what cost?