In order to accommodate the change of the front camera position for the new iPad Pro and iPad Air - from the portrait edge to the landscape edge -the entire charging & pairing mechanism had to be redesigned to work within this now very crowded space. We designed the Apple Pencil Pro to work with these new designs. The users of these new products also have the option to use Apple Pencil (USB-C), with low latency and high precision at an even more affordable price. So, two Pencil options for the new designs.
Of course, we've continued to support existing Pencil options for the existing product designs. In fact, each model has a choice of two Pencils.
So, the changes were necessitated by physics but we've still tried to keep it as simple as possible.
Best,
Joz