Self-replicating robots are enough to substantiate (motivate? create?) the Fermi paradox, and those can probably be achieved in a reasonable fraction of a reasonable species' lifetime, from foundations that can all be motivated by short term concerns. Humans will be there in a couple centuries, if we don't destroy civilization on the way (but that's the boring resolution to the FP).

I've read the Bobiverse series too :-). Maybe the question then is, do intelligent species have the will to invest the capital and labor required when there is no payoff in those decision-makers lifetimes? I think there are individuals who do, but I think it's an open question if societies can.

Human societies already undertake multi-generational projects. For an easy example: cathedrals. We seem to have fallen out of the habit in the last few centuries, but historically it hasn't been that rare. We would only have to be slightly closer to rationality to make it commonplace.

Another example https://en.wikipedia.org/wiki/Uffington_White_Horse

That's called the percolation hypothesis: https://www.universetoday.com/articles/beyond-fermis-paradox...

I think this is a particularly human-centric perspective on the idea. Do you think ants have the same issue now?

Or, concretely, migrating hoverflies. Interestingly they don't appear to be colonial.

Not really human-centric, but intelligent life-centric. Given that the discussion (by this point) was about intelligent life communicating across the universe, ants aren't very relevant, unless you think they're about to start building spaceships.