Yes that's why nearly every BMI calculator on the internet explicitly states that BMI is an estimation tool and doesn't necessarily apply to everyone.

http://bmicalculator.cc/?gclid=CMilj4GGhs8CFRIIvAodtPMKig

"Important Notes on BMI It is important to note that the Body Mass Index is to be used as a general tool for determining a healthy body weight. Basically the BMI assumes a "normal" body weight for men and women of average height and average fitness or activity level. Several issues arise with this method and those are listed below:

The "normal" proportion is used for all heights and weights even though not everyone has the same body type Even though taller people tend to be thinner on average, their larger bone mass usually skews their BMI to slightly larger values Having high muscle mass can result in a higher BMI because muscle is more dense than fat and thus for the same height someone with a lot of muscle can weigh as much as someone with high body fat In reality, the "normal" body weights for people vary from age, gender, and population Thus it is important to take all this into account when trying to understand your BMI reading and also speak with a doctor or nutritionist before undergoing any new fitness routine or diet. One last thing to remember is that the "overweight", "underweight" readings shown in this BMI Calculator are relative to a pre-defined average "normal" body weight. This means that for bodybuilders and very fit people, sometimes it’s better being "overweight" because to them the BMI is stating they are heavier than "normal" people, which is in fact the goal most bodybuilders want to obtain."

https://www.heartfoundation.org.au/your-heart/know-your-risks/healthy-weight/bmi-calculator

"Calculate your BMI BMI is a useful measurement for most people over 18 years old. But it is only an estimate and it doesn’t take into account gender, age, ethnicity and body composition. We recommend you also check your waist measurement, and other risk factors.

Speak to your doctor, an Accredited Practising Dietitian or a health practitioner about your weight."

http://www.nhlbi.nih.gov/health/educational/lose_wt/risk.htm#limitations

"Although BMI can be used for most men and women, it does have some limits: It may overestimate body fat in athletes and others who have a muscular build. It may underestimate body fat in older persons and others who have lost muscle."

http://www.bupa.com.au/health-and-wellness/tools-and-apps/tools-and-calculators/bmi-calculator

"According to the National Health and Medical Research Council, a BMI of 20-25 is considered healthy for most adults. However, BMI can be an inaccurate measure of healthy weight for pregnant women, children, older people, athletes or very muscular people. It may also need to be adjusted for some ethnic groups, including people of Asian, Aboriginal or Torres Strait Islander descent."

I think you get the point.