I don’t disagree with your main point (the complexity of these solutions seems to outweigh the benefits, at least right now). However, I’ve felt that way about many developments in web technologies over the years. I certainly never imagined that we would tolerate Electron, for example, which makes a desktop app by wrapping a browser and a web server, complete with a hefty memory footprint. And yet Electron is behind many wildly successful projects, not the least of which is Visual Studio Code. Long before that, so-called AJAX techniques seemed like a way to seriously complicate pages with minimal interactivity needs. But here we are.
Or to put it another way, if the barrier is just complexity, there’s always someone willing to fill the gap with a library or framework.