we should lower everyone's base damage

No, inflation means that everything is worth so little you need a lot of it to matter. It is typically applied to currency when there is a large amount of it being introduced to an economy. A lot is introduced, making all of it worth less.

What you are suggesting would lead to inflated damage in a way. That would mean it would take so much of it to matter that nobody would bother and just go strait tank. That is poorly worded but you get the point.

What I think needs to happen is what is happening. Tanks need ways to prevent large amounts of damage for a ahort time. Things like Galio's new W and Braum's shield accomplish this. In the tank rework I am hoping to see more of that.