Some examples of healer action usage found during "current content" in the form of P10S, a savage fight that contains one of if not the single most intense healing check in this game: Harrowing Hell.
Yes, that is every healer dedicating over
50% of their total action usage to their level 1 basic attack spell. Yes, that is highly optimized play, and no that isn't the normal experience for most healer players, but the difference between the highly optimized healer and the more realistic savage healer is not going to be very different. Having a handful more GCD healing casts throughout the fight is not suddenly a more engaging experience, and even if it was, your reward for being an exceptional healer should not look like those dogshit action usage spreads.