I am of a firm belief that there is an existing middle ground between what we got with Limited Blue Mage and what would've worked with a normal job that Blue Mage could've been. Hunting down spells for usage could've still been part of the job. Yoshida explained why they didn't do it and it was an asinine explanation to me. The desire to avoid players feeling like they have to have certain spells to play with others was wild when that sort of thing had been present since ARR launch. You needed Provoke to tank as a WAR, forcing you to level Gladiator, you needed Swiftcast as a healer forcing you to level Thaumaturge, you needed your job skills for literally every job forcing you to do your job quests (the amount of White Mages at max level back in ARR without Cure II was way too damn high). Point is, it's been present since the beginning, it's still present in some ways even now that it was wild to even hear it as a concern for BLU.

Hunting down the spells and filling out your book is part of the appeal of BLU. Now, whether or not those spells should just be reskins of existing ones is another discussion. It's a MMO and job balance is always scale. I don't think anyone in good faith can say with a straight face that a job should be identified by how absurdly OP it is or that it should be when placed in a multiplayer environment. Fun shenanigans BLU should have, but overshadowing other jobs doesn't have to be one of them. I absolutely believe the job could be balanced, still fun, and still have spell hunting be part of it while simultaneously being a normal job.

As for why I personally don't enjoy Limited Jobs? The biggest one being my friends who loved Blue Mage before it even existed in XIV wants to main it and they cannot. They can't play the MSQ as Blue Mage. They can't run roulettes as Blue Mage. They cannot play current content as Blue Mage. They cannot play Blue Mage in Field Zones such as Eureka or Bozja. They cannot play Blue Mage in any Deep Dungeon. They cannot play Blue Mage in PvP. They cannot play Blue Mage in Ultimates and they cannot use Blue Mage in normal Duty Finder situations. In order for them to play Blue Mage, they're restricted to solo play in the Carnival or are forced into preforms parties in limited situations or under undersize rules. Blue Mage is also always behind in levels and aren't given attention, if at all, until nearing the end of the expansions life cycle. For someone's favorite job, it doesn't make for a great experience.