There was once a time in League where the exact opposite had happened: fighters were as tanky as tanks, and had comparable crowd control, but also had significantly more damage, and so out-performed them. Hecarim, Jarvan IV and Vi were at the forefront of this, as their versatile kits allowed them to out-gank tank junglers and act in teamfights faster than the enemy team could react to them. Tanks, by contrast, felt slow, weak, and generally ineffective, so many players asked for changes to that situation. Riot's response to this has been to give most tanks target-agnostic damage and durability-to-damage scalings, in addition to even more crowd control than before. As a result, we have fallen on the other side of the fence, where tanks are now capable of applying both damage and crowd control more reliably than fighters.
Despite this situation being the flipside to one of League's previous problems, the fundamental problem remains the same: tanks and fighters are not being differentiated well enough, to the point where one class can end up taking on the functions of the other. It's all well and good to characterize tanks by their CC and fighters by their damage, but when each class has elements of the other, by definition there will always be a degree of overlap. This can also be seen with champions switching from one camp to the other: when Rek'Sai got her damage nerfed, Riot officially treated her like a tank, and only when they realized she had turned into a stun bot did they turn her back into a diver. Galio was officially updated with the intent of being a tank, but he is now being balanced as some kind of fighter as well. Whereas in most cases, turning a marksman into a tank, or an assassin into a support, would require a complete kit overhaul, turning a fighter into a tank or vice versa can often be easily achieved with just a few number tweaks, often without changing the champion's personality either.
I think the only durable solution to this, beyond just rebalancing tanks and fighters, is going to require making much clearer separations between what constitutes a tank, and what constitutes a fighter, so that it should no longer be possible to switch from one to the other with just a few surface-level balance changes. This is something the Tank Update should have aimed to achieve as its central goal, but instead it only further blurred the lines between vanguard and diver. At this point, I think we're all well aware of the dangers of giving tanks "satisfying" damage, as it simply ends up turning them into damage-dealers, and so I think it would help to take a ton of damage out of tank kits, including their target-agnostic damage. Similarly, we need to stop defining fighter contributions by the CC they can apply, or the amount of damage they can soak up for their carries, and should instead focus on making damage output their prime asset. Right now, I suspect one of the major obstacles to this is just that fighters can't function properly in an environment saturated with cheap, reliable, AoE hard CC, and working on clearing that out would work wonders for the class by allowing them to deal damage a little more reliably. Just as with giving tanks damage, giving fighters CC or utility "just so that they can contribute no matter what" is a slippery slope that ultimately fails to address the main issue it implicitly admits to: that if the fighter weren't loaded with those kinds of effects, they wouldn't be able to reliably contribute, even though damage is meant to be their core contribution to a team comp.
or
as their first item. Is Leona a bruiser? How about Braum? Is Amumu a bruiser? See the issue?
His Q needs to pass through minions. It doesnt have to slow its full amount if it passes through minions, and it would help braum be more than just a sub-par support.
Her passive needs to proc on her empowered auto attacks as an AoE (similar to cleave).
His AoE needs looking at. Making non-champions take increased damage from it would be nice (which can be achieved by making minions take the full damage and not reduced damage from extra rings).
Iunno how to do this with nunu. Hes spammy enough it might not matter though.
His empowered autos need to be turned into an AoE cleave (an actual cleave; a wide swing from side to side creating a cone shape. Imagine a titanic hydra proc but centered on shen, alowing him to deal damage to the entire row of melee minions with one attack).