Thanks for confirming and hope a fix will come soon.
I did file a bug: FB22063128
As for the view hierarchy, I've since found that the amount of flicker seems to be dependent on the amount of pen strokes you do before you zoom. If you draw heavily on the entire "paper" before zooming you do eventually reach a state where the flickering doesn't stop and continues forever.
Topic:
Developer Tools & Services
SubTopic:
Xcode
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