[Recurecur]

Technically speaking, none of what you wrote is relevant today. (To pick a major nit, CSS was always meant to be able to re-skin a site completely, hardly "minor".)

Web development has ballooned into a capable, flexible and highly complex beast. It is evolving (understatement) but it can be used to produce very complex apps now, witness the Google productivity apps.

All that said, true native apps provide a superior user experience if done well.