All the past cultures that have monuments that still stand built them to last

Highlighting the distinction between the minority rule and the majority rule. If 1% of people decide to build monuments to last millenia, there will be monuments from thousands of years ago. If 1% of people decide to be carefully conservationists and only consume what the land/ecosystem can support... say goodbye to that ecosystem.

Great analogy and this is the challenge of humanity

Yes you're correct, certain ruling psychopaths wanted the future to remember them forever and as a result used slaves and domination to create long term artifacts with extraordinary narcissistic effort.

I wouldn't call that being "smart as a group"

However I think Ozymandias is a good reminder here

All the cultures that were smart in the 5-10 generation planning scale got wiped out in the short term by the ones that weren't.