You'd think it would too since apple openly advertises how good the newer hardware is at AI. No idea where the above user got the idea that they had no ability to do that.
Not that it'll change any iSheep minds but it takes around 30 seconds to generate an image on the best iOS hardware and blows through battery.
So they would have to do an online implementation like every other shitty AI app.
I'm not sure where you're getting the idea that Apple doesn't allow this. There's overwhelming evidence that they do.