The main claim that dark chocolate has health benefits is true. Even if the article linked to this claim is made by Jason Katz, the operations manager at Popcorn for the People, who has no background of being a doctor or any of that sort. He goes and sites hsph.harvard.edu which is a reliable source for anyone doing research. Even when he is pushing a product he is listing many different ways dark chocolate can benefit you. Some examples are protection against free radicals, aiding your cardiovascular health, and improving cognitive function.
On WebMD it states how it does have health benefits, but in moderation. It states “Dark chocolate does have some components that offer health benefits. But it's fairly high in calories, fat, and added sugar.” While it has its upsides it also has its downsides which people need the exposure to. WebMD also states how it can protect your heart, reduce the risk of diabetes, and even improve your vision.
Dark chocolate is far healthier and has many health benefits, but when all is taken in moderation.
https://www.webmd.com/diet/health-benefits-dark-chocolate