First of all, my company just released a private beta for a large "desktop class" web application where our client flat-out told us to ignore Internet Explorer, to not use any Flash (audio playback is a big part of what it does), and to concentrate our efforts on creating the best possible user experience on Chrome, Safari, and Firefox. So much for "no one would hire them".
Right now it makes a lot of sense to only target WebKit browsers simply because it's the only decent rendering engine that's available on decent mobile phones. Zepto could easily support a mobile version of Firefox or IE once Firefox catches up in terms of performance and size and IE catches up in terms of support for HTML5, CSS3 and other emerging web standards.
Finally, stating that "web developers don't understand that distinction" sounds slightly derogatory, don't you think?
Right now it makes a lot of sense to only target WebKit browsers simply because it's the only decent rendering engine that's available on decent mobile phones. Zepto could easily support a mobile version of Firefox or IE once Firefox catches up in terms of performance and size and IE catches up in terms of support for HTML5, CSS3 and other emerging web standards.
Finally, stating that "web developers don't understand that distinction" sounds slightly derogatory, don't you think?