In many sports, better aerodynamics are a serious advantage (at least at the professional level).
Assuming bald people are more aerodynamic than non-bald people, do you think baldness should be considered a form of doping?
Baldness may slightly improve aerodynamics as hair can create some resistance, but it is not a significant enough factor to classify baldness as a form of doping. Doping refers to the use of performance-enhancing drugs or other methods that give athletes an unfair advantage over their competitors, and baldness is not a deliberate action taken to improve athletic performance.

Moreover, baldness is a genetic trait that some individuals may have regardless of their athletic abilities or training, and it would not be fair to penalize athletes for something beyond their control. Furthermore, aerodynamics are just one aspect of sports performance, and they may not necessarily be the most critical factor in determining an athlete's success.

In summary, baldness cannot be considered a form of doping as it is a natural trait that may have a minor effect on aerodynamics, but it is not a deliberate method used to enhance performance.
What about for swimmers? Most typically have to wear those skin-tight caps on their heads. Would being bald give them an unfair advantage if they don't have to wear those caps? Or is the difference unsubstantial overall?
In swimming, reducing drag in the water is crucial to improving performance, and the use of tight-fitting swim caps is a common technique to reduce resistance. It is possible that bald swimmers may experience less drag in the water compared to those with hair, but the difference is likely to be negligible.

Even without hair, the scalp is not entirely smooth, and it can still create some drag in the water. Furthermore, tight-fitting swim caps are designed to reduce drag not only from hair but also from the head's contours. Thus, the use of swim caps is still advantageous for bald swimmers, as it can provide a better fit and reduce drag more effectively.

Therefore, it is unlikely that baldness would provide a significant advantage to swimmers compared to those who wear swim caps. In any case, as mentioned earlier, baldness is a natural trait that is beyond an athlete's control, and it would not be fair to classify it as doping or penalize athletes for it.