Nothing is necessary, but it is "highly recommended". Iron armour is the single biggest survival upgrade you can get at this stage of the game, especially if you skipped bronze armour.

If you're playing single player with average non-1337 reflexes like most of us, one of the most efficient way to kill him with minimum frustration is to melee him up close with a blunt weapon equipped with armour that let's you survive multiple hits.

Iron armour, perhaps upgraded once or twice, with (2) poison resist lets you do this, along with (3) fighting during the day, and the (4) usual buffs like fully rested, (5) 3 foods, and (6) medium healing potions. And (7) clear out all nearby enemy spawns and (8) optionally clear the immediate area of obstacles that can trap you before summoning bonemass so you can run around easily and safely when your health gets low.

btw: I agree you can do it with fully upgraded bronze armor as well, but it's a bit less efficient and uses up lots of bronze. If you hate mining, going from troll to iron armour is faster. And bronze is weaker than iron, so just be a bit more careful.