Most people don't have time/resources to test every possible interface for a free website.

That is true. I did not want to sound entitled, it is a free for-fun project after all. Just wanted to bring awareness about UI events to other hnews readers

It is allowed, in general. But some apps/websites don't play well with it. In this case, the creator, while developing the site, chose some UI events which don't fire with a mouse on a phone. I.e. the "hold" action on a sound.