It is probably out of scope for the article, or maybe too much on the opinion side, but the Flash developer experience is pretty horrendous.

There are too many ways to mix UI created code, time-line/movie clip stuff, and actual ActionScript code. It can make for some nightmare projects. At least this was the case a couple of years ago when I unconditionally stopped working in Flash.

XCode is not perfect by any means, but way better than flash. It finds the right balance between interface building in a GUI and straight-up coding. Objective-C can be weird, but less weird than ActionScript. Oh, and XCode is free.

So, regardless of the business side, or even the end user experience side, I (and I think most developers) would choose XCode and Objective-C over Flash and ActionScript.