Or perhaps, even wider than that, they want to remove flash from the web by making sure n% of web-capable devices don't support it.
This. Apple has absolutely no interest in promoting the de facto monopoly of Flash on the web.
The simplest argument in favor of Flash support on the iPhone (and The Tablet, and everywhere) is that Flash is, by dint of its popularity and ubiquity, part of the web. But the best argument against Flash support is that it is harmful to the web as a whole to have something as important as video be in the hands of a single company, and the only way that’s going to change is if an open alternative becomes a compelling target for web publishers. It’s a chicken-and-egg problem. Publishers use Flash for web video because Flash is installed on such a high percentage of clients; clients support Flash because so many publishers use Flash for web video. Apple, with the iPhone, is solving the chicken and egg problem. For the first time ever, there is a large and growing audience of demographically desirable users who don’t have Flash installed. If you want to show video to iPhone users, you need to use H.264. Apple isn’t trying to replace Flash with its own proprietary thing. They’re replacing it with H.264 and HTML5. This is good for everyone but Adobe. And yes, I know Flash does much more than just play video. But that’s the main thing everyone is talking about when they talk about Flash not working on the iPhone — video. And when you talk about other uses for Flash, you’re talking about serving as a software runtime, and whether you like it or not, Apple has a clearly stated opposition to third-party software runtimes for iPhone OS, and that policy seems to be working out pretty well for them.