Shadowflare wasn't just an AOE ability. It and energy drain pushed scholar to have significantly higher potency over a minute than white mage, which was problematic because scholar was good enough at healing to make the difference in healing output irrelevant. There was no way Sch was getting to another expansion with the DPS, utility, Nd healing it had. And because making a healer unable to keep up healing for some content is unacceptable, and scholar had a core identity of utility, the dps abilities had to go.
I actually wince when people say protect going away is dumbing down content. Protect only affects overworld content in any meaningful way, so it going away just means you no longer need to cast a spell once a run just to cast it. Like if you find the interaction of protect and rezzes seriously interesting that is... valid? But I don't think most people would want things to be designed to your tastes.
I don't think most people care about potency that much. That matters, but only if you are really petty about not being the best at everything or if the gap is huge. For most people who care about potency they will just change to the higher potency healer, nbd, and people who just are salty scholar isn't the king of healers should 100% be ignored. The bigger question is 'what will healers be doing in fights?' Scholar had a lot going on in addition to its rotation but unlike astro it didn't do most of its things all the time, but in reaction to events, so it having similar downtime to astro MIGHT be a problem. Astro got more complex in almost every way but people have an anchoring bias so it is understandable that cards that SEEM to have more diverse effects would be better than cards that all do the same thing. Trying to card match while also getting a card good for your best dps actually requires more thought than the old system because it can actually require mid fight judgement calls as you are now judging cards along two axises that are competing and risk losing an axis if you reroll for the other.
But a lot of the way healers play really comes down to fight design. The more I read arguments for healer panic, the less convinced I am, because I read the concerns and only have the conclusion of "why do you care?"
Is miasma+bio actually more interesting than a single spell? You tossed em both out together immediately every time anyway... you didn't lose a choice or something to think about, you lost a button... No one liked drawing spire or ewer, they were straight dps losses you mindlessly threw out or converted, a purely player negative rng. Ect. And a complex rotation would require a lot of oGcd things to make healing complex, meaning that old SCH rotation wasnt just oppressive for its dps but because it locks them out of making content with more intense healing requirements.