Trying to follow this tutorial on a localhost WordPress environment created with wp-env, I found that the main "collections" and "models" parts aren't working at all (in both Firefox and Chrome).
Running wp.api.loadPromise.done(() => { wp.api.collections.Posts(); }); in the console, I get the output Uncaught TypeError: this.preinitialize is undefined. Please update the tutorial (or fix the bug if it is one) to include how to fix this error.