When future cockroach geologists look upon this artifact they might speculate it was a throne for the giant creatures that used to rule the planet :-)

You assume they might know or appreciate chairs and thrones. More likely they see it as an ancient monolith.

Well, they may recognize the shape of the chair as being similar to the stations at the end of the ancient transport system the precursors created. But since that system of tubes was too small for humans to travel through, it must have been something from an even older culture that humans co-opted and used in their ritualistic worship of the rectangle deity.

Reminded me of https://news.ycombinator.com/item?id=21653567

Why? It's durable you can clean the chair and reuse it without throwing it away and creating a new chair.

Because it implies an end to humanity on this planet that does not also incorporate an end to that titanium chair. That any physical object could outlive humanity means that humanity will end far before it should.

When should humanity end?

I don't think he was thinking of this in such a draconian way.