You could argue just as well that this headline should be "Scientists say warm weather may slow down the spread of Covid19." But neither headline gets to the p

You could argue just as well that this headline should be "Scientists say warm weather may slow down the spread of Covid19." But neither headline gets to the point of what the article is actually saying, which is that it is too early to tell, and they will be monitoring to find out. The original headline doesn't introduce biased thinking.