Some more Apple Pencil thoughts:
I do have to give it to Apple that they over do things when it comes to things like digitizers. Their iPad pro cap touch layer polls at 120Hz while others are happy with 60~70Hz. Apple Pencil is polling data at ridiculous 240Hz, which out does even Wacom's pro digitizers (200Hz) and goes way beyond other consumer level pens (Wacom @ 133Hz, N-Trig @ 120Hz).
Now we can argue whether that is even worth the trouble since even 133Hz for consumer grade Wacom gives you over twice the data rate of what the most mobile LCD refreshes at. Why bother polling at that speed? I've never personally noticed any lag difference between my Tablet PC pen and the Cintiq pen (33% faster polling). So IMO, the 240Hz is way past the point of diminishing returns.
I think this approach might be taken by Apple because most iOS ink software does not dynamically interpolate between data points (Procreate being a significant exception). They simply "connect the dots" between the point, in which a higher polling rate would help out tremendously. But many Windows and OSX art apps does aggressive interpolation that applies Bezier curve to the data to make smoother curves for your pen input. Compare say Photoshop CS1 pen performance with CC or even CS4. Or simply click off "smoothing" checkbox for your brush setting in Photoshop. It's a huge difference. To me, having the software and hardware muscle to do that negates the need for such high polling rate. Obviously Apple engineers disagree.
But it's an interesting point of difference of how Apple vs others approach hardware design. Even if the higher specs does not make practical difference for end user, Apple likes to do it, put a bullet point on it, and then charge for it. smile emoticon