OP, healing in this game is not 100% uptime job, you also have to do other stuff like for example DPSing or CC'ing mobs with a dmg aoe spell like WHM have.
Depending on healer, some healers has to heal most of the times while white mage for example could dish out DPS comparable to tanks DPS if not higher.

In Wow you are healing non stop, it is not needed in this game (yet), you have a lot of downtime between refilling tank HP.
Alliance raids and raids in general are other story, depending on a team you are playing with, sometimes you will find yourself doing absolutely nothing for a big part of the duty if you want to heal only. There is no need of a healbot in this game, this game does not allow custom UI, developers are not supporting mods in any way because that would be unfair for PS4 players.