Good comment, Siebe.
Yes. There were materialists then, just like today.
But there were also yogis like Alara Kalama and Uddaka Ramaputta who did not have the ten types of miccha ditthi and were on the “mundane eightfold path.”
– That is why they were able to cultivate jhana.
Of course, they were not aware of the anicca, dukkha, anatta nature of the world, and that is why they could not get to Nibbana.
– Upon Enlightenment, the Buddha thought about teaching his new-found Dhamma to those two yogis, but they had just died.