Apple Pencil won't fire pointer events when tap rapidly

I want to use Apple Pencil in Safari via pointerEvents, but it seems not working properly. Sometimes it does not fire pointer event when I tapped rapidly. I found similar issue in here and using touch event seems workaround this, but I'm confused this is a bug or intended.

If it's intended, how to detect Apple Pencil via touch(or pointer) event? Or is there any solution without these events? Thanks.