I was re-reading the PHB yesterday, and spotted a major oddity: all the fighting classes get Extra Attack at 5th level, but all apart from the Fighter get more than that.
The Ranger and the Paladin get spells.
They do, but the way spells scale with slots, those 1st level slots have backed off in relative effectiveness a little, so the 2nd level slots are largely scaling of the existing ability 'spellcasting.' It's nothing to sneeze at, but it's not quite just 'getting' something out of the blue.
The fighter, ranger & paladin all get their attacks scaling with proficiency bonus and extra attack, of course, but the fighter's Action Surge also scales dramatically when he gets extra attack, so he is getting a little something more at 5th, because of that synergy.
Looking at it in in context I'd say that Fighters get so much 1-3 that they are already ahead of other similar classes by 5th and the others get a bit more to catch up.
Let's see, by third a Champion fighter has: 3d10 HD, all armor, shields, simple & martial weapons, two skills, two saves, Fighting Style, Second Wind (1d10+3), Action Surge, & Improved Critical.
By third, and Oath of Devotion Paladin has: 3d10 HD, all armor, shields, simple & martial weapons, two skills, two saves, Fighting Style, Lay on Hands(15hp), Divine Smite, & Sacred Weapon. OK, not in that order, but that's just to map them closely to what the fighter gets. It doesn't seem like the fighter gets more, does it?
Of course, the 3rd level Paladin also gets Spellcasting (3 slots, 1st level), Oath Spells, Divine Health, and Turn the Unholy.
And, of course, the 3rd level Fighter also gets, uh, to pick whatever alignment he wants.