this affects such a small amount of people in practice and is not related to the obesity problem. yes if you are less than 10% BF your BMI might be overweight. this isn’t why obesity rates are high. for almost everyone BMI is an excellent starting point
It caters to a very specific body-type.
Highly muscular people are usually classified as "obese" according to BMI.
That such a deeply flawed measure achieved mainstream acceptance is quite the achievement.