Don’t know where you read that....maybe it only applies locally. Vanilla has been the number one seller forever
It was probably around 1969 as I worked at a snack and icr cream parlor, a huge one, that Summer. I am sure the manager told me butter pecan was the most popular but I think I also read it somewhere too.
I just looked it up and the site I used said vanilla number one, chocolate number two and butter pecan third. At least it is still up there with the top ones.
The only reason why vanilla is the most popular flavor is that whenever a customer at a restaurant orders pie or cake with ice cream, he is served vanilla. Restaurant’s don’t carry any other flavor.