The author makes some decent points about localStorage generally, but I think really misses the point on what makes Wordle so successful and endearing. It was built as a side project for a very small audience and just happened to have massive, organic growth. If Josh Wardle had thought about all of these described use cases in advance, there's a much higher chance that it never would have gotten off the ground as a side project. Additionally, the massive growth would have presented much harder (or at least much more expensive) scaling challenges, whereas with it being entirely client-side it is much easier and cheaper to scale to millions of users.