I think everyone is missing the most important part. He recommended this rule change from the future.

I’m a high school and college ref. We don’t differentiate between attacking / defending when considering a hand ball. My rule of thumb, regardless of the written rule, generally speaking is the did the hand play the ball or did the ball play the hand. And if the ball played the hand, was the hand in a natural position and did the offender have time / ability to move hand or play the ball some other way. That’s always been my criteria for deciding a handball.