I'm starting to think that it would take replacing basically everything that's happened on Web frontend development since XMLHttpRequest with an alternative system that's still standards-based, platform-agnostic and Web-centric, but designed from the ground up as a GUI toolkit instead of a markup language for hypermedia formatting.

Because with the current status quo, the platform that dominates everyone's mindshare is HTML/JavaScript/CSS. Which has a really rudimentary concept of UI controls, and human interface guidelines that spend 90% of their effort on begging people to manually implement usability features that we used to get for free with native GUI toolkits. And I think that we might need to get away from that mess before it's possible for anyone to have any energy left over for worrying about HCI on the level that we used to in the late '90s and early '00s.

As long as you can draw pixels, developers will create "unique" apps just to be different and stand out from the crowd.

The only solution is heavy moderation. But very few players have market share to force developers to do what they say.