Don't like Blue Mage? Here is how to convince SE to change it...

[Reinha]

What's the difference between going to a roulette and getting Halatali, and going into Halatali as a BLU in a premade party?

It's the same content, so why is one taboo and the other one is alright?

One option gives a reward that is relevant to end game (tomes) or gets a job closer towards end game (xp). The other option of doing Halatali as a BLU gives xp to a dead end job that cannot be used in any relevant content. It can't be used in roulettes, normal or hard mode raids and trials, Centurio Seal hunts, Aquapolis/Uznair maps, new beast tribe quests, HoH, Eureka or the next part of Main Scenario. Those are things people can take their alts to whenever they want to accomplish something of value while they enjoy different kinds of gameplay. Alt jobs are useless if they can't be used to progress your character.

We can already go solo a bunch of open world mobs and unsync dungeons for no reward. No one does it because it's not fun or worth it, regardless of job.

[JohnSpawnVFX]

One option gives a reward that is relevant to end game (tomes) or gets a job closer towards end game (xp). The other option of doing Halatali as a BLU gives xp to a dead end job that cannot be used in any relevant content. It can't be used in roulettes, normal or hard mode raids and trials, Centurio Seal hunts, Aquapolis/Uznair maps, new beast tribe quests, HoH, Eureka or the next part of Main Scenario. Those are things people can take their alts to whenever they want to accomplish something of value while they enjoy different kinds of gameplay. Alt jobs are useless if they can't be used to progress your character.
Except that's not what I'm asking. Why is old content bearable as a roulette, but doing it as a BLU suddenly becomes "old content? ew"? It's the same content in both cases. Why does one get a pass and the other one is taboo?
We can already go solo a bunch of open world mobs and unsync dungeons for no reward. No one does it because it's not fun or worth it, regardless of job.

So the argument now is "It's not fun for me, therefore it surely isn't fun for others (because apparently doing it to level BLU and get skills for it isn't a valid purpose) therefore it should be changed/delete"?