The worst part of these changes, to me, is that they can't really be salvaged by patches, either - it's a fundamental rework to how the system functions. The only thing that'll let me keep playing is if they revert the cards back to their original purposes. Although the dps numbers might ultimately be the same, numerical value doesn't represent how a class feels to play.
I'm not sure what the rationale behind this change was, honestly. Given AST still has utility with the damage boost, I think it's supposed to be aimed at meta-raiding parsers who just ultimately care about higher dps numbers and faster clears, rather than actually using the cards in creative ways? But the fun of AST wasn't in how big you could make the numbers go, it was the illusion of versatility and the choices you made regarding who you gave the cards to, whether you burned them for the buff, whether you converted them to Minor Arcana, and whether playing something was worth it using up the buff vs the risk of not playing anything while you wait for the ideal card.
Plus, there was the situational nature of the cards, too. AoE Royal Road might've been useful in raids, but single-target potency and duration were more useful in dungeons. Even Spire had its uses, like clearing big dungeon pulls and the DPS weren't using Tactician/Goad, and Ewer has saved many of my pug raids when my cohealer wasn't pulling their weight and I needed the mana boost to output consistent heals and raises. Throwing out a mindless Balance wasn't as entertaining as choosing to give the Arrow to a SAM or a BLM, and same with giving Spear to a DRG or MNK or BRD. Sure, it wasn't as optimal as Balance, but it added a level of decision-making that kept it fun.
Same with other abilities, too: Lady of Crowns gave me a decent amount of wiggle-room with its instant heal; Time Dilation and Celestial Opposition were super versatile in how they synergised with other buffs; choosing when to use Collective Unconscious since you were immobile for it (which I guess you can still do, but now you can also do it as SCH and WHM, so it feels less like a benefit of playing AST).
All of that's gone, now. Major bummer.