It is also an irrelevant number since almost no kids get severely ill with COVID-19 regardless of being overweight or not -- a far cry from what happens if one is older. Once this obesity works its way with time into older populations in India and China, they'll have big problems with it just like we do. (That assumes no draconian crackdowns on diet.)
BTW, the article states "nearly 108 million children and more than 600 million adults had body mass index (BMI) above 30, which is the threshold for obesity.
Even if that number is up to 1 billion total, that's not 50% of the world is "obese".
50% figure doesn’t come from this article. But the US isn’t the only country with obesity.
Look around and you’ll find articles stating that 50% of Europeans are also obese...