Leatherhead
Possibly a Idiot.
Why are you comparing apples to oranges?
Instead try comparing Totem and Berserk Barbarians, with and without a feat that enables bonus attacks. [emoji3]
You can't compare a class ability to a feat. The whole point of feats is that they're added on top of everything else; a character with a combat-related feat should do more damage than a character without one. I mean, the frenzying barbarian could also be using Polearm Master. It's like comparing a naked character to one with magic weapons. You need to compare class ability to class ability (and even then, most of them aren't 1:1 comparisons.)
Don't shoot down this math "as apples and oranges" so quickly. This is basically the same match up as a Battlerager VS Berserker comparison, given that the Battlerager's bonus attack is also a d4, and they get to use any weapon with it.