However, if your server is doing other work, it might be useful to be close to users even if the data isn't. This is why fly.io sponsors stuff like Phoenix Liveview or Laravel Livewire.
You mentioned Liveview and Livewire. Both are great and they would work equally well in any context, not exclusively a server less front-end.
I would propose that switching to a more efficient programming language (i.e. not using Elixir or PHP) and investing in better data structure optimization would result in equal if not better performance improvements than investing the same amount of time wrangling data replication issues and infrastructure maintenance caused by edge compute.
To the point of the original article, modern web development remains the same: start with a single server, server-side render your content, and expand when the need arises. What we're talking about in the comments is performance web development for geographically distributed audiences (for instance, if you're building a global social network).