Besides the single rear armor hit from the 222 you can clearly see that they pen the jackson quite regularly from the front. Which indeed makes it vulnerable to light cannons, even from the front. (This does ofcourse not mean that a 222 is a counter to it, it just proves how poor its armor is. And thats its biggest weakness.)
Are you for real? You understand that being vulnerable to a 222 is not equivalent than a 222 having a 20% chance to pen? Going by your logic a king tiger is vulnerable to a t34
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