Asklemmy

Seems likely to me the lunar lander will be there for aeons to come. The pyramids are also still there. The library of Alexandria may have burned, though I don't think that was inevitable, and many of the written works and treatises from that era still survive. Euclid's elements is still mathematically correct.

Consider also the negation though -- the burning of the library of alexandria still affects us to this day. Aristotle's views on women and Christianity's views on homosexuality still persist. Colonialism and slavery over the past millenium has negatively shaped the lives of billions. These are all actions by humans with enormously negative consequences that reverberate in the present. Surely we must admit that these agents had meaningful lives.

And there may have been countless more such catastrophes averted, which we don't know about because the lack of something bad happening is not terribly newsworthy. But people who stopped such far-reaching catastrophes must surely have had meaningful lives.