I actually like the idea of GUIs being represented in a markup (whether that be XML, QML, GNOMEs new Blueprint (which is kinda a markup language I think?) but I also thought display postscript was elegant so maybe I'm backing the wrong horse

I think the whole world sails on that ship and MSFT just wants to catch up. Their most darling developer tools since 10 years ago are mostly by web and for web: Typescript, VSCode.