of course by the time we had the ability to do von Neumann Probes our anthropomorphic assumption of time scales may have changed.

How much would human life span need to increase for a von Neumann Probe to seem reasonable. I would think a life span of 600 and you're thinking, sure I won't get to see it through, but my allotted genetic offspring that I am allowed at age 500 if either of my other two have failed might.

If you expect to live past a few hundred years it isn't clear why your lifespan wouldn't be indefinite. The prerequisites for achieving the former appear to be more or less the same as those of the latter.

requirements change with purpose.

a "kilroy was here" sign has different purpose than "eat at joes".

is it enough to say "hi, your not alone" ? would we actually want to encourage discourse, or visitation.