During COVID, we've seen stocks that were previously thought to be incredibly low volatility become highly volatile and decrease in value. And on the other side, we've seen stocks that were thought to be aggressive growth and high-risk become steady growth stocks. The companies are the same, but what happened? Why did everything change?
The explanation isn't very complex or even interesting truth be told. But essentially, COVID is attacking the public, preventing them from congregating or working closely together. Thus, companies that require lots of manufacturing and have factories full of workers are going to take the biggest hits if COVID forces the factories to close. Whereas companies that don't require people to work in close quarters are going to operate as normal, and while their revenues may fall due to decreased consumer spending, they are still operating at full or near-full capacity.
The DOW Jones is usually considered low volatility because it consists of stocks involved in manufacturing and industrials; these stocks are easy to predict because they don't change their operations very much, so they're traditionally easy to track. Whereas the NASDAQ is a stock index full of technology-related companies, and tech stocks are usually considered more volatile and difficult to predict because they can change their operations so quickly. In fact, most big tech companies keep their projects secret to the public until they are ready to unveil, but this would be impossible to do with a manufacturing company because they can't build secret factories.
During COVID the markets have been reacting really weirdly, hence the title of the article you're reading. When bad news about the virus is announced (i.e. increase in positive cases, delayed vaccine trials, record high daily cases, etc.) the DOW Jones goes down while the NASDAQ goes up. And I haven't seen any business news adequately explain this yet, but it's the same explanation as above. The DOW Jones is no longer safe because all of the companies inside it are involved in manufacturing or have long supply chains, and the companies are severely impacted by COVID because of factory shutdowns during stay-at-home orders or the supply chains are being disrupted. Yet the NASDAQ is full of tech companies that don't rely on manufacturing or supply chains.
So a good rule of thumb, if a company can survive with 90% of its employees working from home, the company will perform well during COVID.