I’m the same way. I have eczema and in general dry skin and spend a lot of time outdoors. I can’t recall ever having poison ivy reactions.
Worst I ever get is a little pinkness and itch that’s usually gone the next day. I’m still careful about touching the stuff, though.
When my brothers were little, about maybe 7 and 8, they were bragging to their friends about being immune to poison oak, and rubbed it all over themselves to prove it. To this day, all you have to do is call them up and whisper, “Poison oak,” into the phone and they’ll break out like anything.