> I can see how someone lugging lots of muscle mass around would want their own number
Healthy people with high BMI are not how they are by accident, they don't care about their BMI because they know why it's high and they know it's not an issue
exactly. the number of people who have "high BMI" due to muscle mass and general fitness is utterly trivial when compared to number who are straight up fat.
it's a nothingburger; whether you use BMI or Body Roundness or whatever, most USA-ians are fat as hell.
Healthy people with high BMI are not how they are by accident, they don't care about their BMI because they know why it's high and they know it's not an issue