IMO this is a mistake. The most popular platform in the world does not allow using a polling loop. You can hack things to simulate it but eventually you'll run into where this will break for you. Better to start with something more forward compatible.
I don't know what that means, but just because something else doesn't use a polling loop doesn't mean it's a mistake or the wrong fit.
Something like this so simple there is likely to be a lot that gets done inside the main loop, not the least of which is drawing into the buffer which is most of the point.
If we also believe that the desktop GUI apps are a thing of the past, and in the future everyone wants only web apps, we'd want to pick a C library for the UI which allows building for the web, for the future scenario where we have to port the app to stay relevant.
The scenario might not materialize, but having a contingency plan sure feels nice.