I agree, which is why I think this species might be the start of something amazing: https://en.wikipedia.org/wiki/Larger_Pacific_striped_octopus

It's also a bit of a chicken-and-egg problem: if they were raised by their parents like all other more intelligent animals, they wouldn't need to be as intelligent as they are in order to be able to relearn "octopus behaviour" without help from other members of the species.

In Stefan Wul's SF novel "Nyourk", octopi evolve to become the Earth's dominant species, which was quite prescient back in 1957, when almost nobody knew octopi to be intelligent. :)