Thought about RDM's utility

[wereotter]

Unrelated note, I disagree highly with your signature. RDM has never been a melee-centric or melee-heavy job, and in fact usually spends more time casting in the entries for which it is available; the fact that it has better melee equipment or physical stats in older entries is, for the most part, consolation for limiting their access to stronger spells. The Red Mage has only ever been about combining White and Black magic into something more, with swordplay being largely vestigial; in fact the "iconic" use of a rapier is actually quite recent in series history, around FF11 I think. By comparison, it's been a "turret" as long as it has had Dualcast, introduced in FF5.
For a job focused on combining sword and sorcery, you may mean Rune Fencer, Spellblade or Mystic Knight. But first and foremost, the Red Mage has always been... a Mage.

Only a handful of games in the series even have red mages, so your assertion that red mage has never been a melee job (then proving that it has been a melee job) seems to only be thinking of one title as the end all and be all of the job.

Consider the full history of the job:
FF1: all-rounder job limited in access to higher level spells with fewer cast charges than its black and white mage counterparts. Had access to medium weight armor and swords.
FF2: non-existent
FF3: starter job that was outclassed by other jobs pretty quickly. Acted similarly to FF1 in that it had access to a few spells and more swords and armor.
FF4: non-existent
FF5: continued the trend of being able to use low-level magic alongside being a melee fighter. Unlocked the Dualcast ability that helped red mage keep up with magic damage of other casting jobs, and being even more powerful when used by other dedicated casters.
FF6: non-existent, though one could consider Celes a red mage archetype. She learns magic naturally, but most of her spells are weaker than Terra's in the long run, and is highly competent with a sword.
FF7: non-existent
FF8: non-existent
FF9: no playable red mages exist
FF10: non-existent
FF11: this is the title that you seem to be referencing, and I expect is where you are trying to distinguish red mages from the other jobs. I never played the title, but from what I understand while being the most recent implementation, it is also the outlier of what the job is.
FF12: non-existent in the original. The Zodiac Job release continues the trend of giving the character a wide variety of spells, along with some unique magic, and includes a mace and shield as weapons.
FF13: Lightning is very close to being a red mage, and her initial paradigms include offensive caster, healer, and melee fighter, all of which she is equally competent at.
FF14: this game
FF15: non-existent

So to that end, explicit red mages, and if we expand the definition to include Celes and Lightning, have always been competent fighters with a sword. Depending on your playstyle, it's also highly likely that a player would rely on sword attacks first and magic as a backup for enemies like flan that need magical damage or as a backup healer. Just as likely as someone who views them as a caster first and melee fighter once their mana runs out.