Earlier quoted context omitted.
Crazy idea that I'm sure isn't an original thought: instead of adapting the languages to deal with abstracting the idiosyncrasies of each OS, change the OSes to expose a universal API to make everything else lighter. I guess that's also kinda Docker or QEMU or V8, but also https://github.com/solo-io/unik if you think about it differently. In other words: hey, Lisp Machines were an excellent idea back then, but they s…
Cross platform 'windowing toolkit' APIs are what's missing. At this point I'd be happy even if Microsoft, Apple, and UNIX likes (who would probably just implement any free open standard anyway) could agree on even ONE such interface. Postscript as a UI language? Fine as long as they all do it. HTML5+ as a UI language? (E.G. like the failed HP Fire or Firefox) Fine as long as they all do it. Some new thing that isn't…
One really obvious example (maybe no longer current - it's been a while since I spent any time on Windows) is that OS X windows are responsive even without focus. So you can scroll around background windows just by hovering without having to click first. Windows doesn't support this.
The bigger problem is that the data structures for menus, chrome, and the rest are completely different. An OS X menu is nothing like a Windows menu is nothing like a Linux menu.
There are systems like Tcl/Tk and Qt which act as middleware between GUI descriptions and specific OS bindings, and they kind of work. But they force devs to learn a separate intermediate language and (IMO) they look crude compared to real native apps.
Of course there are also business reasons why GUI convergence won't happen.