IIRC, iOS 10 is being developed under a new model, based on backlash from the iOS 9 slowdowns on older hardware.
iOS 9: Build all the features, test them on old hardware, start culling the ones that don't work at all. Stop when it's 'ok'.
iOS 10: Build a baseline set, then add features incrementally on all hardware unless they don't work well.
See the difference? In the former, you start with a slow ass system, and then remove things until "Well that's better". In the latter, you start with a snappy system, and add things until "Well, hmm. This is starting to lag."
These two approaches do *not* end up in the same place. 'Better' and 'oops' are subjective and based on where you start out.
I have some hopes moving forward that older hardware won't suffer quite so much.
My other brain is hung like a horse too.
#IRC isn't old school.
Old school is being able to say 'finger me' with a straight face.