I read the thread, WHM has not lost its identity. It is one job where you are THE healer, the ABSOLUTE healer in the game, with good DPS output and good MP management. AST cannot, will not, and never ever going to match that. But you also need to read about what AST is, a job with dual sects, who can provide a similar ability of white mage or scholar, it gives player a choice which sect they want to enact to complement the other healer in your party. And AST has a nice set of cards to make up for their lack of benefits in other areas compared to the other two healers.
As much as AST can simulate the other two healers, AST IS NOT WHM and IS NOT SCH. They do not have the full capabilities of either job, just a few abilities to closely provide the benefits of the other two jobs. AST selling point is the cards, which now, are pretty good, not in OP way, but at least decent and can be great if the RNG favors the good cards.
I think you are fairly intelligent to see that SCH and WHM, each has their own unique selling points that AST cannot match, maybe closely simulate, but not excel in any of them by a great deal. If I want to be THE healer, I simply come as WHM, a job that has the best healing output in the game bar none, sorry AST, good try. If I want to be the DPS/Shield healer hybrid, then SCH is my defacto job. And if I want to come as hybrid healer who can bring decent buffs to the party, AST is the job. If people here are too blind to see the distinction, then dunno what else to say.
At the end of the day, AST is A HEALER first who has some decent cards that can buffs the party. AST IS NOT A BUFFER job who can heal here and there. The same can be said to SCH, they can DPS yes, but they will not outDPS a Summoner.... So now, we have THREE different healers in the game. Be happy, be grateful, be thankful, less bickering, and less finger pointing. Stop playing negative nancy, bitter betty, and doomsday daisy lol.