Seriously it is showing on alexa that this website is between 500 and 600 in alexa traffic rating, right now around 570 for example, which is A LOT. There is only 569 other websites in the whole world that gets more visitors than coinmarketcap. Is 400 million dollars a lot of money? Sure it is, we are talking about almost half a billion dollars. However think about binance and how much they can earn from this. They can make the website look prettier and show all their own data as the best website in the whole world and they can put binance ads all over the place and basically control that traffic towards themselves.
Is there a possibility that as soon as it is sold the number of people who visit the website will go down? Of course there is, maybe website will get worse and that is why there will be less people visiting, however that doesn't hange the fact that binance basically pays for its own advertisement for free while still owning the whole website and also makes sure that other exchanges do not put ads there neither, so not only they are promoting themselves but they are also blocking others promoting.
Binance can improve the AI that coinmarketcap is using to get correct data. Right now CMC is just presenting inaccurate information that junk exchanges using their bots to make it appear like they have volume but their AI can't recognize its bots so it ranked these exchanges on top. And the team who has no idea are making negotiations to them for IEO.