The difficulty of Normal Content in this game needs to increase.

[Nobuyuki_Sanada]

But is that due to the difficulty of the dungeon, or the players you are playing with? I think you are misunderstanding the two. If you have DPS that are playing optimally and tanks that use proper mits, your job arguably becomes the easiest of the 3. When its the latter, you are scrambling because you are technically the only role that can "save" it with your tools. A dps dies to an aoe? Other than a redmage/summoner, only you can save them XD. Heals, shields, etc. are more needed when enemies live longer and players take more unnecessary damage. With your logic, every form of content is hardest on healer because if the players are the worst things imaginable, more heals, shields, and rezzes are needed which healers can supply.

Even with proper mit and dps playing optimal it is not a matter of just using 1 skill. You need to know your kit, using the wrong heals will get your tank killed even with mit. I'm not saying it's crazy difficult but it is much harder for a player using the job for the first time to learn. If you think you can just afk and spam heal then you don't heal very much. People expect you to know how to dps and heal at the same time regardless of experience. Nobody gives the healer the benefit of the doubt when it comes to experience. While nobody cares if the dps are not playing optimally, or if the tank isn't using mit.

My logic does not state that, in fact it is the opposite. Once a healer knows what they are doing aka more experienced, they are then introduced to content that has a lot less healer responsibility. Raids will use raid wide aoe's but that is usually cured with 1 maybe 2 spells. Dying to mechanics that instantly kill you can't be mitigated by a healer and nobody blames a healer for that. Everyone blames the healer if a tank dies during a big pull. DPS have the most difficult job during endgame content because they have to try and perform the most complex rotations at the same time as doing mechanics. They also have not been prepared for this since before they just used the healer as a crutch in content all the way to endgame.