Low skill healers = Miserable time.
High skill healers = Actual demigods.
The PvP-focused healers I know tend to play several different healers and get to reap the benefit of fast queues. They also do silly stuff like going to an enemy capital and seeing how long they can survive tons of people attacking them.
The PvE-focused healers I know tend to play very well and make a rather noticeable difference compared to pug healers.
I’m just of the side that my engine isn’t built with healing in mind, so it is in everyone’s best interest that I leave that to someone else because I understand it’s an entirely different mindset and set of skills required to be good at healing in WoW, compared to say, FF14 where most of the time it’s just being a DPS with a few buttons specifically suited for predictable damage events.