You also forgot the first pull in Bardams - You can pull all the way to the Stone Faces.
But the vast majority of the pulls still are double pulls. Sirensong Sea has only double or single pulls (7 pulls total if I recall correctly), most of the pulls in Violet tides are double or single pulls (first, second and everything past the princess - maybe even the two after the first boss, unsure), the second, third, fourth, fifth, sixth and sevenths part of Bardams are double or single pulls, the first pull of Doma is a double pull and honestly, I already named twice as many 2 group pulls as you named 3 group pulls and don't really feel like further arguing the semantics of the word "rare" because that's entirely beside the point.
What I do give you is that 3 group pulls are more common in level capped dungeons. But even there, they aren't the majority.
