The current prototype of createDragStream() uses streams of Pointer Events to create a drag stream. Pointer Events are not natively supported by Safari, but can be polyfilled.
To receive pointermove events, an element must set its touch-action to none. In native implementations, an ancestor view can have touch-action: none and its pointermove listener will receive events. However, there's a bug in the polyfill that won't propagate pointermove if a child has touch-action set to something other than none.
Thus, instead of setting touch-action: none for draggable views and touch-action: auto others, we omit touch-action entirely unless it needs to be explicitly set.