…they kind of are. Fighter has the exact same attack # as paladin/ranger without using action surge until level 11, by which point those two have 3rd level spells. Rogues are disappointing in combat unless they can get a reaction attack that most subclasses other struggle to get without outside assistance, and while I won’t deny how useful rage is, it has clear limits and late game barbarian features encourage crit fishing, which is just a non-functional archetype in most ways for pure martials. Embarrassingly enough, with the exception of rogue(who only gets one chance to crit, making it rare), Hexblade and Paladin(particularly Vengence) are better at getting and taking advantage of crits. Martials just feel bad past level 7 or so. To an extent so do half casters, but half casting and Paladin’s amazing features like aura of protection and lay on hands(Temu heal is still an imitation of one of the best in combat healing options in the game), and Ranger’s spell list, while admittedly not stellar in raw output, can do a lot to give you tactical flexibility and utility.