Honestly he's right. More and more people are building "tank" getting Titanic Hydra+ black cleaver and stacking HP or getting titanic Hydra + sated devourer and facerolling every AP mid, ADC, AD top with wreckless abandon. They recently added these weapons that make tanks do more damage, revamped some tanks to be even stronger and increase their survivability. The point of "Tanks" in videogame history is to be large, in charge, slow, lumbering, nigh unstoppable titans. Where's all this damage nonsense coming from?
You increase damage, you get squishyer
you increase tanking, you lose damage
you get tougher, you get slower
you get faster, you take more damage
that's normally how games go in the balancing region.