16GB is small enough to require active storage management, even for fairly casual users. It's becoming a real issue.
16GB iPads are a poor (or at least mediocre) user experience, even for ordinary users. It's contrary to Apple's ethos to continue making them at all.
It's even sillier when you consider that everything else about the baseline $499 model has been drastically improved several times over since 2010, and Apple has taken steps that clearly reduced the utility of the 16GB baseline (retina graphics, full HD video).
32GB should be the new $499 baseline. It's way past time.
I know some users. I don't know if they are ordinary. I think they are. My parents in their 50's. A grandmother of 80. Some friends which are 30 with a very average computer literacy.
Every one of them took fast with the iPad (that's how Apple is good), but no one of 'em'll fill 16gb of space.
They've all had storage issues on 16GB.