Players just have to hold back from following through in the tackle. It all comes down to tackling skill.
It’s the same with marking, there is skill and an element of strength involved in using hips and shoulders instead of arms to hold your ground in a marking contest.
What the AFL should do, which they won’t is educate players the alternative tackle in such a situation and then filter this to the coaches who should teach them how to do it.
And if you can’t tackle somebody that is too big and need to resort to such tactics then too bad.
Watch the Grundy thing again, all he had to do was pin the arms and hold him there. He resorts to slamming him down with the tackle which is stupid. If he actually just hold his arms and then drops his knees in the tackle Brown can’t do anything and the result is the same without the unconscious player.
2 is the right amount.