Because young people don't die often, the requirement to be a "leading cause" isn't very high. According to the article Covid ranks 8th in causes of death with

Because young people don't die often, the requirement to be a "leading cause" isn't very high. According to the article Covid ranks 8th in causes of death with about 1,300 deaths in the 0-19 age range last year. Not saying it isn't an issue, that's still 1,300 dead kids, but the headline seems (to me, at least) a bit sensationalized.