The and this feels like one was actually intended to suggest that tweaking font size feels like something that should be user controllable.
In terms of the 44px - the original iPhone and iPad had different PPIs, and the current iPhones and iPads also have different PPIs, so the 44px has never mapped to a constant physical size across all devices.
In actual fact the iPad mini has exactly the same PPI as the original iPhone (163) which was presumably what the UI guidelines had in mind which means that 44px should be perfect for it. 44px on the iPad will actually allow more area than the smallest possible area.
This is probably why pretty much every iPad app has been is completely usable on the iPad mini.
Certainly the fact that existing apps are fine undermines any suggestion that everything needs to be adjusted - if anything the evidence is that nothing does. While I'm sure there are some exceptions to that it'll be relatively few and the best approach is probably to scale everything and have a little more space than the minimum on other displays rather than to try and code individually for each one.
In terms of the 44px - the original iPhone and iPad had different PPIs, and the current iPhones and iPads also have different PPIs, so the 44px has never mapped to a constant physical size across all devices.
In actual fact the iPad mini has exactly the same PPI as the original iPhone (163) which was presumably what the UI guidelines had in mind which means that 44px should be perfect for it. 44px on the iPad will actually allow more area than the smallest possible area.
This is probably why pretty much every iPad app has been is completely usable on the iPad mini.
Certainly the fact that existing apps are fine undermines any suggestion that everything needs to be adjusted - if anything the evidence is that nothing does. While I'm sure there are some exceptions to that it'll be relatively few and the best approach is probably to scale everything and have a little more space than the minimum on other displays rather than to try and code individually for each one.