I'm completely convinced that cosmetic/skin purchases are by far the best way to make a sustainable continuously updated pvp game. Nobody feels bad about not being able to invest money to be able to win, it encourages (and funds!) active development of the game and its visuals, and rare/cool skins and associated animations can be delightful to see even on other players.

I think it can create new jobs in the future (and maybe now?) as well. If you had an open market where aspiring artists could design and sell skins for something like Fortnite, with the developers taking a cut of the profits, it could be worth learning Photoshop/CAD and just selling assets. I think the Unity store is like this.

It would be challenging for the developers to make sure 3rd party skins were balanced for competitive play.

You mean like camo giving an advantage?

The reason for the backlash on StarWars was because you pay for (some of) the game, where as FortniteBR is free. And I believe StarWars made it so you can pay to be the more powerful characters, where as I believe FortniteBR doesn't contain any Pay-to-Win