[moring]

I think quite the opposite happened, just not on X11 level. The web browser is essentially a thin client nowadays. The fact that you have full client-side scripting is one thing that was IMHO a bit underdeveloped in classical thin-client systems because with that you can mask network latency much easier (though, admitted, I don't know a lot about how X11 handles this).

[moomin]

Don't agree at all. The web browser is essentially a standardized computer on which to run your fat client systems like SPAs. The browser can run arbitrary computation locally.