Obviously, where we are going is just exposing all the system resources (like file systems, GPUs, USB ports etc) to JavaScript/wasm APIs and replacing the whole GUI stack (X/whatevr, WM, etc) with just a browser. A browser is just a cross-OS compatibility layer now (and this is quite cool as you can now run considerably exotic OSes like Haiku or Solaris and use almost all the stuff other reople do). I have also heard ChromeOS is probably going to replace Android at some point.