I think the big problem with tanks is that they're getting too much damage.

One of the big tradeoffs you are supposed to be making as a tank is that you give up the potential to deal damage but make up for it by being extremely durable and having lots of CC. But as someone who plays a lots of tanks ( mainly Nautilus and Poppy in the toplane ) I've noticed that this tradeoff isn't nearly as bad as you think because there are tons of ways to counteract that weakness.

On Nautilus for example you get ridiculous amounts of extra damage from an early Doran's Ring pickup, the AP from runes, Grasp of the Undying, Abyssal Mask and Sunfire, all of which stacked on top of one another. At this point you kind of feel less like a tank but more like a bruiser because you die just as fast and deal just as much damage.

Wayyyy back in the day it wasn't this way. When you were a tank your damage was pitiful but you traded that for the ability to feel absolutely unkillable, especially when you were fed. That feeling is pretty much gone now because everyone can kill everything extremely fast and tanks just don't feel all that tanky anymore and I think that kinda sucks. When I play a tank I want to feel like one, not like a Garen or Jax with more CC.

Perhaps one of the ways to make tanks less problematic of a role is to simply give them less sources of damage - less AP that they can get from runes and items ( or maybe even reducing their AP ratios instead of buffing them all the time ), making a Resolve keystone that doesn't deal damage and is restriced to defensive supports, or balancing a whole class around two items, Sunfire and Cinderhulk, by frontloading so much extra base damage and waveclear into them that you simply can't choose NOT to take them. And the absolute last thing the tank role needs is a point and click true damage nuke that scales with HP . . .