Right tool for the right job and all that jazz. We don't need more flamebait like the OP.
We went this route too and hoped we could re-use lots of code we already had but, as you say, the right tool for an iOS app is Objective-C. Un-JITed JS inside a wrapped app with a zillion Objective-C stubs using the DOM in a view-like manner its not meant to represent just doesn't do it.