Truly Barbaric Barbarians

I feel like the Barbarian class in D&D is so named only for style, and not because the class lends itself especially well to non civilized cultures.

In fact an accurate representation of a D&D Barbarian would be a Fighting-Man that chooses to clothe himself in furs and lighter armor instead of heavy, fitted metal armor. (Fur would have to be relatively cheaper in the lands where this barbarian came from for this to make sense)

The D&D Barbarian doesn't match any known history

The term Barbarian is a misnomer anyway, it was a pejorative used by the Ancient Greeks to mean anyone that didn’t live within the Greek city-states, and a mocking of their language, which the Greeks said sounded like “bar bar bar”.

However in the real world, truly barbarian-like cultures have been contacted by more technologically advanced ones. The Aztecs and Mayans created high civilization, government and religion, but technologically they were in the Stone Age and could not survive contact with European explorers. The same is true for Native American tribes in North America. Even the Gauls were technologically inferior to the Romans, until the Romans pacified them and spread their knowledge and manufacture.

However the stereotypical Barbarian culture, the Vikings, weren’t Barbarian at all! Despite their reputation for raiding and warfare, they had Iron and Steel technology, and actually subjugated the post-Roman Britains.  I actually think that it was the Britons that reverted to barbarism after the Romans left the Isles.

 The D&D Barbarian doesn't match popular fiction either

The popular image of Barbarians has nothing to do with history, but comes from a fiction series written by Robert E. Howard, which is a pure fantasy yet has captured the imagination of generations of readers and fantasy enthusiasts, and is now the template by which we judge all subsequent barbarian heroes.

A D&D class that tries to fit the mold of Conan the Barbarian comes off poorly, as the most accurate depiction is the Barbarian class in the 1e Unearthed Arcana, and though players took to it with enthusiasm, most of the class’s features and almost all of its restrictions are house ruled away - in other words breaking the mold it was made to fill.

The 5e Barbarian class bears no resemblance to Howard’s heroes nor any to history either. The 5e Barbarian is well clothed, well fed, takes to warfare by choice, and may or may not have some kind of outdoor woodsman or hunting experience. They also optionally get a spirit animal, like a Native American, somehow.

The D&D Barbarian is too civil

The best way to see this class, in the current D&D timeline, is as a strong, physically adept Warrior with a penchant for furs, lighter armor and larger weapons, whose ancestors once scrabbled in the wild to survive, but who himself has had social support since birth.  Sounds more like a mercenary or Landsknecht than a tribal nomad.