i guess at this point, making poise do something would actually have a pretty major effect on the game's balance, esp. if it were balanced without it. it'd probably be a lot more work than just making it do something, they would have to go through and make sure that decision actually makes the game better instead of worse
There is even weapons in the game that say they damage poise and have poise damage. The counters for poise are there, however these weapons also don't work.
So my character could have 0.0 poise and then I put on iron flesh. I can tank every hit without being stunned as though I had 100 poise. When your anti-poise weapons hits my iron flesh, they do absolutely nothing. I'll still tank every hit.
So Iron Flesh basically creates infinite working poise with a trade off at being slow but with fast rolling because I have no armor on. So what's the point of investing stats to wear heavy havel armor with slow movement, slow rolling 60+ poise and it's absolutely useless?