Dunno, may be you are right. With the advance of flexbox there finally would be a possibility to do good old delphi-like anchors for responsive UI. In a WYSIWYG editor. Without spitting out hardly maintable brittle javascript which simply manages layout (something which is framer.com/other designer tools can do right now).

So far the facebook stack and react-desktop seems to be the best candidate for that description, but I don't neceserily think people would focus on getting it to the desktop styling. Universal Material UI (or similar?) probably would overtake that approach.