What we write about says much more about ourselves than we realise. What you've written here is itself is a legacy of sorts. It smacks of ego to picture oneself as being in the vanguard of a species that has seemingly done so well, when actually it hasn't done very well at all. Ego goes hand in hand with greed.
What we have achieved, is near extinction, by our own hands, and that wasn't necessary at all.
Imagine how different things would be now, if we hadn't kneecapped real humanity enhancing, humanity future-proofing advancements all along.
I know this intimately because I myself have lived for technological advancement, working in the forefront of technology, including on space programs as an attempted innovator, coming up with practical technical solutions for all kinds of things. I would say of all the potentially good ideas I personally have had experience of developing, and others I've had the pleasure to be involved in, very few have come to any fruition, because of being kneecapped by lack of funds.
No-one wants to fund anything that doesn't offer them privelige, in the current unsustainable system driven by nothing but greed.
The project of Nikola Tesla to deliver free power and something like internet connectivity to all people 120 odd years ago being defunded comes to mind, as probably the most significant knee-capping of technology event we ever saw.
The reason it isn't talked about much, seems to me to be ego. Folk with ego don't like being told uncomfortable truths, things to be ashamed of, so they just try to cancel the information, writing stories like yours instead.
Do you even realise how vain and ego driven it sounds, to talk about leaving some kind of memorial on the moon, when humanity is dying all around us? I read another article by someone else high in the scientific community in Medium on the same subject yesterday, Avi Loeb. Is this what science has become, nothing more than an attempt to write your own versions of the history of a species in process of committing special suicide?
Many significant negative historical events, things we should be ashamed of, have been cancelled, by a few with egos, who didn't like being reminded what a mess we've made, and are still making of things.
There are many, many more such events, still happening now more than ever. Look what happened to the covid vaccine development. look at the lives unnecessarily lost there, the human cost, of human greed. It started as something intended to wipe out a deadly virus, and ended as a privately owned fiasco, achieving nothing more than making a few greedy people who were already rich, even richer, at the cost of millions of lives.
Greed and ego is being allowed, even encouraged, to triumph over innovation at every turn.
The innovation is there to turn all of this around, but folk such as yourself, who have everyone's attention, will never speak of it, because it offers you no privilege, so on this rock we are likely to end, literally.
If you really personally would like to be remembered as someone who did real good for humanity, you could talk about turning things round, using the humble technology of solar power, by issuing money to all people representing the Joules received by donation from the sun, in advance, as necessary to create the community solar hydrogen infrastructure needed by all people.