The idea of being "Wild" in this song pertains to living that life outside, in the wilderness where as a kid you can often just go exploring, feel like you're going to get lost and not have a care in the world. As we get older, we begin to lose some of that. When I was younger I wouldn't hesitate to do certain things that I look back at now and think about how if I did them now I'd likely be hurt.
This song does both ask and answer that question about whether or not you can still be wild when you're older. To me, I think age is a state of mind. I always have that idea in my mind of "I need to do this now because when I'm older I'll be too tired". But at the same time, so long as you keep telling yourself that you never really stop doing things because of your age.
With melodies like Lisa Loeb and a bit of that sound like the song "Torn", this just feels like a pleasant song and it somehow feels connected to nature in its sound as well. There is definitely a vibe about it that could have it on modern radio and I think people might just see it as the surface of going wild but it has those deeper meanings.
If you've ever thought about slowing down or just felt like you didn't have that same level of curiosity or just that you're not learning new things still then this song is for you. "Wild" should serve as a reminder that as long as we're still breathing we can keep going so we should.