Claws have high health and defense, so you need high power weaponry, or armor piercing on lesser stuff, to have a chance. Deathclaws would hit hard enough to kill Super Mutants in 2-5 hits, so the Mutants need equipment, especially weaponry, to kill the Claws before melee combat can start.
Gameplay, which unfair against the Super Mutants, gives at least some idea of what to expect. Mutants would live and die by their intelligence, gear, and whatever tactical advantage they have.
