We already have 3 different standards: HTML, CSS, JavaScript.
These are low level enough, and powerful enough that you can build document, multimedia or application frameworks on top of them. Simple UI tasks don't take rocket science, they take a proper understanding of those three standards, and a lot of discipline.
Re: "Simple UI tasks don't take rocket science, they take a proper understanding of those three standards, and a lot of discipline."
I appears to me you are contradicting yourself. It comes across as: "It doesn't take the discipline of rocket science, but merely the discipline of rocket science". GUI's didn't take "a lot of discipline" in say VB-classic, Delphi, or Oracle Forms[1]: you dragged it to where you intended it to be, and Wazaam, it was there and always there. WYSIWYG was a huuuge time-saver. Now to do it right you have to test on dozens of platforms and versions because they each have a mind of their own. WYSIWYG gave you one central coordinate reference point, not 30 different positioning engines.
Re: "We already have 3 different standards: HTML, CSS, JavaScript."
That's part of the problem, not a solution. They are not domain-specific, for one.
[1] They had glitches, but were getting better over time.
VB-classic, Delphi, or Oracle Forms have whats known as drag-and-drop/visual programming. Comparing them to CSS & HTML isn't a fair comparison, unless you compare that to a drag-and-drop GUI that creates HTML & CSS for you.
These are low level enough, and powerful enough that you can build document, multimedia or application frameworks on top of them. Simple UI tasks don't take rocket science, they take a proper understanding of those three standards, and a lot of discipline.