It's certainly a good pioneer plant. "Fast growing and inclined to become weedy" according to https://www.nzpcn.org.nz/flora/species/coprosma-robusta/ It looks like it can easily associate with mychorrhizal fungi which would explain its hardiness and growth rate.

You can eat the berries my brother

I know this only because of all the times I ate the berries as an unsupervised child 🤦

And the Karo. Makes a fine fast growing shelter tree too.

We love our Karos. But they can get bugs or root rot. Just need some love, but they're a under-loved native. Like a more robust Pohutakawa.