First, thank you for challenging my opinion. Having to defend my position makes me think even more about this hot-button issue and will hopefully help me to become a better official.
We don't know how he (the team B player) would have landed had the block been lower so your assertion that he would have suffered the same impact upon contacting the ground isn't really a valid one.
IMHO a lower block would cause less rotation and would not result in the defender landing that way. Regardless, A80 has no control over how the "blockee" lands. What he does have control over its where his block is placed and in my opinion, this block is too high and is a foul.
If we say that you are correct and A80 lowers his target and levys a big stick block resulting in the blockee landing the same way, no foul. I can't punish a player for the way somebody else hits the ground, only for the way he chooses to play the game.
As for the question of a ballcarrier, I would need a specific example (perhaps one from your seemingly limitless video library?). I assume a player from A wouldn't be de-cleating a ballcarrier so it's hard for me to visualize the scenario you have in mind.
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