I disagree but will likely get downvoted on HN as this communtiy does not really reflect the huge set of customers Apple is building these devices for. The Mac is for us. iDevices still for the most part target a broad swath of users (despite the pro moniker) and have to be easy to use and as secure as possible.

Offically suporting sideloading will lead to what we have on the Mac, an official app store that is barely used and compromises the security model and user experience for many major apps. If you give an official channel to bypass Apple policies people will use it for everything. A major part of the security model for example is a third-party (Apple) being able to nuke abusive apps. Also enforcing compliance with certain UI guidelines as the devices evolve keeps things very easy to use. Its possible to have some of the things for sideloaded apps but more difficult to control.