I don't mean to be dismissive vikingkingq but it appears that you are trying fit fluff to make your argument. So all fighters now have formal training and barbarians are completely untrained? Conceptually special maneuvers should be open for anyone to take. Heck I think rage should be open to take. And blasphemy sneak attack too.
Fluff, nothing. The Fighter Design Goals document describes the class concept as:
1. The Fighter Is the Best at . . . Fighting!
the fighter should be the best character in a fight...
2. The Fighter Draws on Training and Experience, not Magic
Fighters master mundane tactics and weapon skills...
3. The Fighter Exists in a World of Myth, Fantasy, and Legend
...In the world of D&D, a skilled fighter is a one-person army. You can expect fighters to do fairly mundane things with weapons, but with such overwhelming skill that none can hope to stand against them.
4. The Fighter Is Versatile
The fighter is skilled with all weapons. The best archer, jouster, and swordmaster in the realm are all fighters....the fighter is typically in a class by itself regardless of weapon.
What makes the Fighter a Fighter is skill, training, and experience. By contrast, ever since they absorbed the AD&D 2nd edition Berserker kit in 3rd edition (and even in 2nd, the Barbarian Ravager kit was described as "to many, the Ravager represents the consummate barbarian-a savage, nearly invincible warrior who fights with unrivaled ferocity" and given the first Rage mechanic), the Barbarian's class concept has been the berserker. In 3.X, they were described as "brave, even reckless warriors...where the fighter has training and discipline however, the barbarian has a powerful rage." In 4e, they were a Primal, rather than Martial Class, whose abilities came from supernatural rage, as opposed to martial training.
Now, let me be clear - I'm not opposed to a Veteran Specialty that gives a Fighter equivalent of Magic-User or Acolyte (maybe giving you a d6 CS die and two level 1 maneuvers), because that represents past experience. If a Barbarian enlisted in the Imperial Auxiliaries, or the Paladin came to the church after a battlefield conversion, or if the Rogue or Ranger is a deserter from the army, then it makes sense that they have some martial skills they've retained. At least then it still represents an investment of time and effort in training, and it keeps the class mechanics themselves distinct. And there's always multiclassing.
But outside of specialties and multiclassing, having a Barbarian use Fighter Maneuvers or a Paladin using Sneak Attack goes absolutely against good design for a class-based game, and it's absolutely the opposite of what the devs are going for. Listen to the panels - their whole drive is to ensure that a Ranger feels and plays very distinctively differently from an Archer Fighter with a woodsy Background and a decent Wis score; which means you don't let class mechanics bleed across classes if you can avoid it.