Whales have been around for about 30 million years
And while they seem to be very smart, they haven't built anything we
would consider technological. I don't know how long octopii have been
around, but they too haven't done anything major in the building area,
even though they are the smartest of all known invertebrates.
As Douglas Adams said, whales and dolphins may show their superiority
to humans by not having all the things we consider the mark of civilization,
as they wisely spend their days just playing, eating, and mating.
It is tough having only one data point to go on for now.