[leokun]

It's very cool and immensely impressive, but the web moves fast and it's interesting to note how quickly previous everything and the kitchen sink and or ui libraries become dated. Just look to dojo, jquery ui, ext.js, jquery mobile, even Cappuccino looks dated (take a look at http://www.cappuccino-project.org/learn/demos/LightsOff/ for example).

Big libraries can't move fast, and can't adapt to all the latest things easily, like reactivity, flat ui, new features like webrtc, persistent websockets instead of REST, etc.

[watty]

And the web will continue moving fast and soon enough "flat" ui will look dated. This is why it can be themed:

https://openui5.hana.ondemand.com/#docs/guide/ThemingFAQ.htm...

[leokun]

jQuery UI can be themed, there's a flat theme, few people use it. Those who do were already using jQuery UI and searched for it.