iOS 3 on any device has a tiny marketshare - Instapaper showed it at less than 1.2% of iOS, and that was nearly 9 months ago. (http://www.marco.org/2011/11/30/more-ios-device-and-os-versi...)

The support matrix for Enyo is here - http://enyojs.com/docs/platforms/ Opera Mini and mobile are just not supported.

You need to draw the line somewhere. 'Broad' support is good. 'Everything' support is futile, for the feature set desired in a mobile application framework, with the resources the Enyo team has.

Enyo is good at creating 'apps' - often things delivered in a PhoneGap-like container or something with defined browser support like Chrome Web Store.

Its probably not the general framework for any and all website development needing to support all platforms.