I beg to differ, all mortars have tendency of squad wiping due to squad bunching.
I also beg to differ, 120mm mortar has 100 damage, 6 AoE (1.1 near 4.5 far). 80 and 81 mortars have 80 damage (so technically can wipe a units), but AoE of 4 (1 near 3 far).
If a squad has full HP, if you consider the fall off damage of a 120mm shell, it has more wipe potential because the damage is equal or more than 80 in medium distance. But other mortars can only kill a model if the shell falls directly on top of a model. For a wipe you need all models to be closer than 1 distance unit.
And besides, this kind of isnta wipe is actually more punishing for non blobbing players.