Apple can't ensure people make good ads. They can't magically force people to become good designers or programmers. The app store itself is evidence of that.
The mere existence of iAd isn't going make people turn out great advertising. It will just bring more crap to our hand held devices.
Your missing the entire philosophy and factual evidence behind this move.
Steve said it himself in the presentation. No one clicks these lame banner ads on their iPhone or any phone for that matter! The philosophy is that they have created an infrastructure that will allow advertisers to create more memorable ad campaigns on a mobile device. They will truly be interactive and have the potential to be somewhat fun (based on the demo). An app within an app basically.
Your right, iAd's mere existence won't turn out great advertising, but if you actually want to reach this large market sector and actually want them to click on your ad and actually want them to buy your product, then what Apple is saying is that you have to think in the realm of iAd. Those lame ads you showed only exist because people accidentally scroll over something or randomly click the wrong section of a web page, I would hardly say they represent successful ad campaigns, only that they are memorable for how lame they are.
The short answer is that if you want to advertise to a growing iPhone/Touch user base, Apple has showed you a far more successful way to do that.
They are saying, "create ads like this, using our software and framework, and people WILL click on it".
If they don't, guess what, iAd goes away because they have no customers.
Ads becoming "interesting and artistic" will not happen because of iAd. The features that Apple touts - animation, full screen, video - this is all done currently on the web. Not every advertiser is Pixar or Nike (Apple partners). You going to get funeral homes, douche commercials, viagra, and Extenze, allergy medicines, and vacuum cleaners. You are going to get every product under the sun. And not all of them will be interesting.
iAd cannot give designers, copyrighters, or CEOs any more talent than they already have.
No they can't. But your still missing the point, if no one clicks the ad on their mobile phone, then what's the point? Apple is making a grand statement that they believe they have found a way to attract mobile users to ads. If you want them to host a simple banner, then so be it. No one will click it.
If you want them to host something interesting, they are banking on your ad dollars being out to good use. If their wrong, well then their wrong.
Creating crap ads is easy, no doubt about it, but what's the point of an ad if no one buys the product?