Oh god, I'm going to have to break this to my daughters this evening.
I think any parent with a child who's an active CP player is thinking two things: "Oh man, I got to break it to my kid" and "Great! Now they'll stop nagging me for a paid subscription"
Sounds like they're having a PR disaster if this thread is representative.
You probably already know, but I'd highly recommend Overwatch in that kind of niche. Similar co-operative FPS gameplay with a more vibrant/interesting backstory/world and characters, and very polished. It's got me doing more gaming than I have for perhaps a decade (heck, it's even good enough to be worth putting up with a non-Steam platform).
No Overwatch for me, I'm on a Mac.
It's never too early to get them started on ESDF.