It's the environmental message it has and its exclusively environmental theme that makes it unique from every other franchise and what makes it the most relevant 90's superhero franchise as we still have environmental problems today. I mean just check out this article:
11 Storylines From 'Captain Planet' That Predicted What the World Looks Like in 2015
I'd be a little more ok with this version clearly inspired by Don Cheadle's version if they also greenlit another animated series on Netflix or something like Voltron. I just don't want to be disheartened that another generation of kids would miss out on what Captain Planet is really about, especially in this day and age.
I think it's a pretty sound consensus that audiences have had enough of depressed superheroes thanks to Zack Snyder's Superman.(That is unless they were inherently depressed like Batman, Punisher etc etc)