>Performance in web apps is not a goalpost for everybody.
But in 2017 startup and companies are starting to understand how fast response times (on a website/web-app) are of critical importance for gaining a good user base.
True, but in my experience bad UI response times are more related to something goddamned dumb like running a series of super expensive scroll events or watching DOM changes for some idiotic reason, more than about raw processing power.
A C solution might make the former faster, but it'd still be a dumb architecture. A cheaper solution than migrating your whole codebase to a separate language and build process is knowing how to deal with events and how to parallelize (or delegate) stuff correctly.
But in 2017 startup and companies are starting to understand how fast response times (on a website/web-app) are of critical importance for gaining a good user base.