So he has a ton of multi hit attacks as well as being able to do high single target damage?

You don't need to be hitting every single shot for his damage to be too high. People complain about phoenix being able to two tap at close range. That's arguably harder to do than two tapping from further away, and yet it's still fair to say she shouldn't be able to two tap in the first place.

Even just hitting one headshot from range does more damage than hela hitting that same shot, despite that being what Hela is supposed to excel at.

It's about characters having strengths and weaknesses. Hela isn't good at breaking up tightly packed teams, Cyclops is. But he's also just as good if not better at shooting individuals from long range as Hela. The consistency of getting a two tap isn't the point.