There are a lot of people, including refs who aren't all that happy with the change. But it's coming down from FIFA/USSoccer. I would guess it's to allow more scoring. But it's the Law now (or interpretation of the Law now). (I don't like the Dan Hurley in the American League, but it's the rule. So you gotta adjust and live with it.)
Yea, there were some big discussions on that one. The CR/AR got it right. Some argued he impeded some of the defenders getting to the ball (which isn't an offside call anyway), but really the only defenders even moving toward the ball was the GK (and he didn't bother him) and Beckerman. Who was actually following James, who came from onside and didn't play the ball either. James may have got in Beckerman's way, but not the player in the offside position. All the other defender where standing there with their hand in the air.
There are 3 items in "being involved in play".
1. Interfering in play. Which means they have to actually play the ball or be the only offensive player who could. That wasn't the case, he never played it.
2. Gaining an advantage. Which has to do with playing the ball off a rebound from a post/crossbar or GK save or a deflection off a defender. That wasn't the case.
3. Interfering with opponent. This one was the only one that could apply. This is by preventing an opponent from playing or being able to play the ball by clearly obstructing the opponent's line of vision (usually the GK's) or challenging an opponent for the ball. He did neither.
Yea, I agree, you gotta call that stuff, even at young ages so they learn.