I did a search, but applying a 1 scale to the model before unwrapping did not work.
The faces A and B are the exact same size. I have applied size scale (control A) in object mode before unwrapping, smart unwrapped with every type of option I could checkmark, and I’ve even marked almost every seam and did a straight unwrap. Still, every time side B is smaller.
There must be something simple I’m missing here.