Since the tank update I've always believed that the sunfire nerf was ridiculously harsh and only allowed updated champions to survive. While Maokai, Galio, Zac, Sej and Cho were extremely powerful as they were compensated to survive the update, most other tanks flailed unless buffed or changed in some way IE Malphite and Sion buffs. While I don't think tanks should have the same carry capacity as fighters or mages, they simply couldn't benefit at all from kills they squeezed out of lane. Top that off with a pretty useless change (extra damage to minions when Titanic Hydra exists), hey presto you have a lot of tanks were straining to see play.
I'm sure the item will need reexamining in the near future, probably when another Ekko/Fizz type champion is able to build tanky leading to all tank items getting nerfed. For now though, glad to see rewards for proactive tanks winning lane coming back rather than merely trying to survive it/ cosplaying as a pincushion.