I'll give an example: let's imagine two healers doing combined damage of 6k in the most current P12S. If the rest of your party is being consistent you can probably clear the fight but let's say a dps dies because they made a mistake > that's a guaranteed wipe to the lack of damage. Now let's imagine that both your healers are doing like 12k combined damage, you would have the chance to clear even with one death. Just cause you're a healer doesn't give you a free pass to doing bad damage and "I'm healing" is not an excuse for it.

And lastly the main reason why there's absolutely nothing wrong with the healer role is the fact that people can play it and even main it but still be horribly bad at it, so that alone signifies that there's a significant enough learning curve to the role to let you determine if somebody is experienced enough or not and clearing one or two fights once doesn't make you experienced or a good healer it just means you cleared a fight once but did you do good? With the majority the answer is "no, you didn't"; did you overheal - "yes, probably more than you needed to"; did you waste your co-healer's cooldowns because YOU overhealed - "yes, I guarantee you did".

Healers are an extremely well balanced role with very fun and intriguing healing kits when used correctly. If you don't have much experience and you think healing is boring then you're either not playing it correct or you're going into content with the incorrect mentality but that's okay the game allows you to play any job on one character, so just swap to something you'll enjoy more. There's no need to "healer strike" but even if you did I'll tell you now that it doesn't matter because the experienced healers and those that just enjoy playing a healer will keep playing and enjoying healers in the game easily and quickly filling any PFs that are trying to enjoy the game.