"A place to grow as an artist and a person or just a site to make numbers go up." Depends on the user, really...
If your friend is one of those artist who uploads 3 pieces, waits 2 week and then makes her first ever news post their "I hate NG! Goodbye!"-post, then Newgrounds isn't for her.
If your friend works on her craft 4-7 hours per week, has some attention span, actually uses the platform herself for a bit to learn how it works, and can muster the courage to ask questions in the forums, she'll likely love it here.
All that aside: If she's not interested in the first place, just leave her be. If she uploads art to the internet, she'll land here automatically after she gets burned by the other sites. I think Tumblr & Instagram(?) are the only other ones that are 'usable enough' so her chances of landing here are 1 in 3. ;)
Combinge
I haven't been here for a long time. But from what I've heard from people talking on Twitter about it and seeing reuploads of NG cartoons on YT as a 12 year old, it's the last bastion of artists communities doing whatever they want for the hell of it