@FeralPony Why tanking isn't fun
Whether this is intentional or not, I don't know, but Riot has painted themselves into the opposite corner of MMOs when designing Tanks. In MMOs, the goal of the tank is to absorb as much damage as possible, constantly drawing aggro so that the DPS champions can do their damage. Rarely do MMO Tanks bring utility that effects hostile units, but either buff themselves or their allies. When compounded with the length of engagements in raids/boss fights, Tanks go unnoticed, because they honestly don't do anything visually exciting. In contrast, Tanks in League tend towards being extremely visually intense. Malphite ults, Braum ults, Leona Ults, Darius ults, all of these demand your attention. These abilities are the greatest bait and switch in modern game design.
The primary goal of tanks in League contrary to popular belief, is not to absorb damage. Lets think about the champions I mentioned before, Malphite, Braum, Leona, and Darius. All of these champions are given powerful, fight changing abilities that have been balanced by their low range. And then because of the low range they're required to have tanky stats so that they can survive. Tank is the secondary role of these champions, not the primary. So the reward for building tank stats is that you can continue to exploit the base values in your kit.
The last issue with tanks is their feedback system. If you're a tank, your job is to absorb as much as possible. But your job is also to prevent the enemy team from doing damage to yourself. So you can theoretically die in a fight and have accomplished your job in a fight, or lived at 100% and accomplished your job. Compare this to the feedback a DPS/HPS gets. You can see the sliders of the enemy team move down faster than yours to know you won, or they didn't and you lost.
Imagine a world where more than 2 champions(Rammus and Galio) are rewarded for being a tank. True tank champions draw aggro not because of their damage or their CC threat, but because they force the enemy team to focus them. If there were more options that let someone pick a true tank, than the off tanks become more rewarding, because you're opting into the off tank role. Right now, if you pick an off tank, you're trading either damage or utility for tankiness, instead of trading tankiness for damage or utility.
Is this solvable? Yes. The only system preventing true tanks from existing is the champup/DNA teams. And I highly suspect as a counterculture to the juggernauts and dive-fighters there are true tank champions, or at least something similar currently sitting in the champion design pipeline.
So the TLDR? Tanks suck because they don't exist.