But this doesn't work on your phone, or on a Windows or macOS device, right? That's what I meant by flexible, X forwarding fits a pretty narrow set of usecases, while on the other hand keeping programs on the clients and data centrally located on a server allows for a whole lot more options for how to interface with that data.
(To be clear, nothing wrong with X forwarding! It's a cool tech and I'm glad you have a use for it! I'm just arguing that it's fine for Wayland to not try to support that kind of thing, because we've got other ways of working remotely now.)
There is not a web tool for every use. And web tools are not better for every use.