And why is that? What facts directly support that opinion?
I think that if that was the case, there wouldn't be an immediate discussion following Jobs' comment on the same thing. If anything, I think the fact that these remarks have made it all the way to this discussion proves that it isn't such a clear-cut answer.
In fact in many areas I'd disagree with the statement that integrated is better. While in some cases simplicity is great, what the hell is the difference between a store with 170,000 applications versus 90,000? If you're saying that the average consumer can tell the difference, I'd call BS. If you're talking about an above-average user, then the issue is moot because they will know how to get the applications they need without hassle anyway.
Not only that, but fragmentation in itself has many levels. Yeah, everyone that codes iPhone applications has to use (somewhat) similar tools and API. However, what's the main draw for an app-maker? If anything, I think what platform a developer writes for has a lot more to do with his previous experience than the current dominant or integrated platform.
Don't distance the developer from this. Consumers and developers, especially in these kinds of micro-transactions, are intimately tied. Things that affect developers DIRECTLY affect consumers, and I don't think it's so easy to draw the line.