Old school example, the Fighter in FF1. If you level up a ridiculous amount, black belts and masters can do more damage. But in realistic terms, fighters have the best damage output. They also have the best defense and probably HP too. Once you get the spell-casting items, they can do nearly anything the spell casters can, except revive dead allies and cast FAST (Haste.)
Yes.
Fighters have absurd hit rate (which affects # of hits, and therefore damage)
They have a selection of equipment unique to them, boosting their Defense stat above any character, coupled with the highest hitpoint growth via having more level ups that guarantee max HP boosts; said defensive equipment also grants them relevant lategame resists
Fighters benefit from a bug which makes critical hit based on a weapon index as they are programmed in the game instead of what critical rate weapons are given; combined with how they hit more often than other characters, they roll crit rates more often as well, and the two best weapons in the game they can use: Excalibur and Masamune, have the highest crit rates as a result of the bug
They have just enough luck to run from battles effectively
Weapons like Defense cast spells relevant to the Fighter's function, in that it casts Blink, giving them extra evasion for tanking bosses that actually can eat through their defense and HP; oh, and Knights, the upgraded form of Fighters, learn Blink anyway
Literally the only weakness fighters have is that they have no early game AoE function. One could argue that always having full armor slots limits what they could do, but I would say that's more of a case of being
too good than not having that option at all and they still have plenty of weapon slots for the variety of AoE magic casting weapons you get.
The optimal party for FF1 speedruns are some combination of Fighters and Red Mages (since Red Mages obsolete the other Spellcasters), and of course a party with more Red Mages than Fighters has never been considered, only whether to bring one or two Red Mages.
