Apple isn't really in the habit of cutting prices (this has exceptions and I'm ignoring various FX price adjustments). They're more about giving you more for the same money. So at some point you'll probably see the same prices but for 32/64/128GB. I'm a little surprised this hasn't happened already. I expect we'll see it next year. 2014 at the absolute latest. Perhaps this would be too much of a constraint on flash chip supply though (IIRC Apple is already the largest consumer of flash memory so doubling their demand would be significant).
I, for one, will happily buy a 128GB iPad.
That all being said, I think there are now three serious missteps in the post-Jobs Apple:
1. The Maps debacle;
2. Elongating the iPhone 5 to create yet another resolution (the relative uniformity of the iOS line with only 2/4 (if you could retina) resolutions was a huge advantage for developers). I really don't see the point; and
3. The Mini. Sure they'll sell millions of them but by that same argument Windows Vista was a success. IMHO 16:10/9 makes far more sense on the 7-8" form factor rather than the "fat" 4:3. Also, 7-8" tablets are moving to be 720p+ and this is below that at 1024x768. The price is also (IMHO) too high.
Google OTOH (disclaimer: I work for Google) I think has a lineup that is starting to make a lot more sense between the Nexus 4/7/10 at some pretty nice price points.
I guess that's a good comparison for this article because the Nexus 7 upgrade from 16 to 32GB is only $50.
EDIT: Two points:
1. I'm not calling the iPad Mini a Vista-level failure. Seriously, please read what I actually wrote (the whole electric car was also a big example of people not reading what I wrote but I digress...). I simply said that selling a lot of something doesn't preclude it from being a misstep; and
2. The whole idea of "excessive profit" with a luxury good is fundamentally flawed. If you don't like it, don't buy it. Ultimately it costs what it costs because the market bears it.
EDIT2: I understand very well why the mini is 1024x768. Perhaps I didn't explain my point very well. My point is that's not a very good resolution for a 7-8" tablet (IMHO of course). IMHO the 16:10 ratio works much better (YMMV) but they have their hands tied.