According to the Letter from the Producer LXXXI Digest, the stated reason for changing the way the card system works was that there have been requests to remove the randomness from Astrologian. I understand that some people did not enjoy the rng of astrodyne or not getting the ranged/ melee card they needed but that doesn't explain why the card effects had to be changed and we have now ended up with only a third of the cards giving a damage buff.
The class will go from being super busy and making you think every 2 minutes to just giving the melee card to your top melee player, same for the ranged card. White mage has always been available for anyone who wants to play a straightfoward healer with astro being an option for people who wanted to get more out of their class, so it seems unneccesary to dumb down the class by removing most of the damage buff cards.
Furthermore, most of the new cards are either completely pointless or have very niche uses. Ewer: ST HoT(astro will have 3 charges of essential dignity, intersection, exaltation + whatever their co-healer has for ST), Bole: 10% DR(all the tanks had their 30% cooldowns upgraded to 40% and 99% of the time they won't need the extra DR anyway), Arrow: 10% Extra HP Recovery(here's a bigger shield for you Mr. Scholar, yay). The only one that appears semi-decent is Spire but even that seems unneccasary considering how many options there are for mitigation/ free heals, both from the healers and from the party.
I feel like the card system should either be reverted to the way it worked in Endwalker or at least change the new cards to be useful/ cards people care about a.k.a make them give a damage boost either via having 1 set of two cards give 6% extra damage, 1 set give crit and the last set give dh or something similar to that. That way we can be excited about all the cards we get instead of having one useful card per draw and two "meh who cares" cards.