Both are necessary. I think the difference is that Group A (keep things running) without Group B (explore new territory) would have kept us in the stone ages. However, that is not to understate their importance: a humanity consisting entirely of Group B would be much more unstable, and possibly have gone extinct.

It's similar to the Rogue Bees: https://www.mrdbourke.com/what-if-you-did-the-exact-opposite...

Although rogue bees (as a small portion of the population) are actually essential to a hive's survival.