A lot of misconceptions about FFXIV come from players who apparently played WoW or GW or some other MMO where basically everyone is a DPS and few people pick healer roles because the healer role is too squishy, and other healing mechanics (eg pots) are cheaper and lack penalties. The Tank who chainpulls is an example of bringing bad habits from one MMORPG to FFXIV.
If you are going to play a game, you first play it like the developers intended it, and then when you see opportunity for
emergent gameplay, that doesn't break the intent of the game mechanics, you take advantage of that. Trying to go straight to minmaxing every GCD just because it's there, is not not smart or efficient gameplay, and certainly isn't fun to play with party members who expect a pro every time.