While I'm not a Fortnite player, I thought Fortnite was known for not being pay-to-win, with IAP being for cosmetic options, not in-game advantages; basically selling digital collectibles you can show off while playing.
I think there is a pretty big ethical differentiation between that and F2P games that have you pay for in-game advantages (with the Wargaming.net model where you pay for in-game options that are mostly not competitive advantages but broaden the scope of play choices [because most of the competitive advantage is compensated in matchmaking] somewhere in between.)
Not all F2P + IAP models are the same.
What exactly is Apple doing to combat the scourge of “free to play”/“pay to win” and in-app purchases? From where I'm sitting, they seem perfectly fine with it (as long as they get their cut).