Any approach that evaluates sports or sports personalities based on net earnings or online following is, by the very nature of the analysis, going to be biased towards wealthier, technologically advanced societies. However, in terms of fan base, you have soccer, cricket, basketball, tennis generally in the top four and then an assortment of more regionally popular sports like US football, golf, volleyball, boxing, auto racing, athletics, etc.

India's population is better than four times bigger than the US.  China's is even larger.  If you want to know the most famous athletes on Earth, you should start with the two countries that together compromise almost 40% of the planet's population.  I guarantee you Drew Brees doesn't make that list.