Tul of the Blizzard - not ignoring resistances

In 3.26 I was running exsanguinate with Doryani on merc and the difference was huge. This league I thought I'd feel the same with I used Tul of the Blizzard but clearly I am not. I can tell the resistance is there.

I made an attempt to show this on The Shaper, the attempt might not be the best. But I think you can tell the DPS is very similar.

Considering Shaper is supposed to have 50% resistance and I don't have any other elemental pen, the showcase should show a significant difference in DPS.

https://youtu.be/HsqfRKleHUw