I find the reactions to healers and AST have been hyperbolic, superficial, and have lacked some depth since the new actions/job guide became available. Like many that might reply to this thread, AST has been my main since it was released.
However; at the end of the day, I'm sorry if you really enjoyed AST but don't any longer. That's a bummer, truly. If you take a step back and try to understand why systems were changed so drastically, maybe you can come to an understanding that it was all necessary for the future of FFXIV and specifically the healer role.
In broad strokes, I like the direction AST has taken in Shadowbringers. The design intentions of the job are very obvious now. Low personal DPS augmented by increasing rDPS.
As for healers in general, it's also obvious now that all you bring is healing/mitigation and a little bit of DPS. Full stop. This adjustment was completely necessary — specifically for the future of the healer role. A lot of the reactions have been to this change. And it's completely valid that losing that greatly affected the feel of AST and for some, took away what made an AST — well — an AST. I would like to posit that the pre-5.0 AST was blurring the lines between healer and support and the changes made were to make AST definitively a healer and not a semi-support job. Again, it's a bummer if you liked that AST filled the vacancy of support role in FFXIV. But WHM and SCH do not have support role capabilities, which made balancing the three jobs difficult. Removing the support role system of AST was good for the long-term outcomes of all healers.
When a fourth healer is introduced, only having those two systems, healing and dps; it will be much simpler to introduce and balance. The tweaks will then come in the form of how healing and dps are contributed. Support/utility are much harder to attribute value because it's like comparing apples and oranges. Since it's hard to determine a numeric contribution to the overall performance of the job, dividing healing jobs by whether or not they even brought utility leads to instances where a job (like WHM) feels completely useless at times. A little bit more on this later... but back to AST for now...
I like the new card system. Taking the changes to cards on its own, I can see why many feel AST has been destroyed. The original design made AST feel like a support role and some people really liked that. A few things to keep in mind is that 1) FFXIV doesn't have a proper support role, 2) The citations of previous card effects being more versatile were only really offsetting the shortcomings of how others were playing, 3) Encounter design unapologetically places DPS above everything else.
(Additional follow-up on the 1, 2, 3 in the first comment)
(Specific Actions feedback in the following comments due to length of original post)