Why do Ghosts kill zerglings in 2 hits?

Something I’ve been thinking about of late, is why do ghosts kill lings in 2 shots? It feels so weird for that unit.

When I think of the ghost kit, it’s always been focused on anti spellcaster, aoe in tvp and in zvt sniping the big hive tech units. Why do they need to kill zerglings in 2 shots if it’s supposed to be their counter? All the other race mid-late game spellcasters don’t even have an auto attack .

I just don’t fully see the point of the ghost auto attack being so strong. I feel like it’s so unneccessary when Terran has a lot of strong complementary options to kill lings. With +3 Hellbats 1 shotting lings, tank AOE being good vs ling bane, mines and planetaries, it feels like the ghosts being able to kill them lings so fast as well is nuts.

Posting as a discussion. Just something I haven’t understood why it’s important for ghosts to have.