Would reverting back the damage formula solve the squishy tank problem?
I'm basically just throwing out ideas, I actually have no idea whether this would help or not, just a wild guess. I was wondering, if Riot changed nothing in terms of items, keystones or champion nerfs, but they simply reverted the damage formula back from:
% armor/mr penetration is calculated first -> flat penetration is calculated after to flat penetration is calculated first -> % armor/mr penetration is calculated after.
I wonder how much this would help tanks be more durable. Since tanks is nearly the only class that builds defense items, this would barely affect other classes(other classes will be a little bit tankier, but very little). This way, they can revert tanks back to the role they were meant to be while letting other classes abuse it.
Since % hp damage is also either AD or AP damage, avoiding % penetration first also allows tanks to reduce the % hp damage as well, except true damages.
Do you think reverting the damage formula would help? Feel free to correct me if I am totally wrong, since this is just a wild idea of mine.
Thank you.

