Funny thing is that that would be ridiculously easy to do.

The iPhone keyboard actually expands the touch radius of "likely" keys as you're typing. They could just program it to do less of that based on purchase date.

But what's actually happening is that nobody bothered to make that feature work with swipe-to-type. If you turn off swipe-to-type your typing accuracy will go up 2x.

Also they transitioned the spellchecker from a fixed dictionary to a stupid AI thing at some point.