>>120659175>When you have 100 armor to reduce damage by 50% but the enemy crits you for 200% damage you gained no reduction.No, you gained 50% reduction because the attack is doing 100% of its damage rather than 200%.
Likewise, if you have 300 armor, you gain 75% reduction because the attack deals 50% of its damage rather than the 100% it would have at 100 armor or the 200% at 0 armor.
Your silly logic makes no sense. Armor doesn't magically become less effective versus crits, they're still reduced by the same amount as the rest of the physical damage you receive.
