> why web technologies will ultimately prevail over native for most applications
All your users care about is UX and features. Native sdks provide more features than web apis, are more powerfull and your users feel the difference. Native sdks are not going away anytime soon.
While I don't think that native SDKs are going away any time soon, there are huge classes of applications where those additional features aren't needed, and even more that can us in between solutions like phonegap. I think that very few applications outside of games really need features that a web-based UI can't provide on modern mobile devices.
Didn't Facebook famously switch from HTML5 to Native for their iOS app? If a company with the resources of Facebook can't do it effectively, I think you underestimate the problem or overestimate web-tech capabilities.
All your users care about is UX and features. Native sdks provide more features than web apis, are more powerfull and your users feel the difference. Native sdks are not going away anytime soon.