It doesn't make sense to me, but I don't have kids or run a school, and I'm in no way prudish or opposed to fun and slackitude, so my perspective on what people under 18 should be allowed to access is no doubt quite different from that of the people who decide what to block.
The thing with the classes is I have a long history of playing pen and paper RPGs, like Dungeons and Dragons. In those games a character's class very often equates with their role. There's flexibility in the way you build your character, but generally speaking Fighters are tanks, Rogues are stealthy surprise attackers, and Clerics are healers.
So when they said you could change your class, my first thought was that you could change your role. Which would've been a huge departure from XC1. When I rewatched the Treehouse video though, I wasn't so convinced that'll be the case. That's a good thing though. One thing I liked about XC1 was the strongly defined character roles.
Also, has anyone else noticed that Alma's clothes and weapons kind of make her look like post-Galahad Fiora? In particular the way her guns are on her back look like Fiora's drones.