We are all headed towards the heat death of the universe with near zero chance for persistence beyond it. (…) With that said, we are the only beings that demonstrate an understanding of that probable future; And are thus the only beings possibly capable of doing anything about it.

You do not really think that, even if some descendant of us still exists at the time of the heat death of the universe (having somehow survived billions of years in a dark universe with no posibillity (to our present knowledge) to generate any kind of usable energy), they will in any way be human? Or even be able to remember or discover that we were their ancestors?

Edit (Addendum): I think even if human descendants should be around at the death of our sun, they will not be able to be called (or remember being) human.