iPhones are almost 'idiot proof' for a lack of a better description. Allowing removal ( or rather hiding ) of the apps will 'break' that impression.
I'm surely in favour of making iPhones/IPads general computers, but that not going to happen. Those legislations from EU are no help.
The only thing I don't understand is the App Store, since today that's the place you go if you have "deleted" say, Notes or Music, and want it back. I guess they'll have to add a button in Settings or something called "Restore App Store."
And while people in general are certainly idiots and will certainly find a way to screw up, I don't think it's going to be a massive big deal to tell them "go to the App store and redownload _____" (plus whatever the way is to put the App Store back). We all know that the way to get it back isn't going to be like, SSH into the phone. Apple will have some way to do it that takes 10 seconds when people call into AppleCare, or literally the first person you see at the Apple Store will know about it.