Someone like Prince Harry saying that Fortnite is a waste of time, is seriously damaging to the image someone might have of themselves playing it. I doubt Prince Harry has got the first clue, and his opinion of it being a waste of time is totally subjective.
It took me probably a decade until I realized that the large chunk of my teens I spent logged in to World of Warcraft were not a blemish on my life. The game had so much depth, it was incredibly challenging, and the social aspect was a huge part of it. My family and our societies negative view of the game encouraged a negative view of myself, seeing as I enjoyed it so much.
Of course you should encourage variety, but let your kid play the fuckin game!