[DmenshunlAnlsis]

So many assumptions here. Maybe they’d be able to, but why would they want to? What’s the point of probing a galaxy that you can only ever explore below the speed of light, at the cost of ungodly amounts of energy and eons of time? Why wouldn’t that same civilization stick within 1-100 light years instead? There is only a paradox if an advanced civilization with high tech is so irrational that they can’t control their breeding and doesn’t care about time dilation and efficient use of resources.

It also assumes that it’s safe to broadcast your presence to the whole galaxy that way. It assumes a lot of unproven ideas and then hand waves at a “sufficiently advanced” species that has only apparently enjoyed technological advancement rather than personal or social advancement. Maybe humans as we know them would spread unmanned probes across the galaxy for the sake of doing it, but I have doubts that humans capable of th feat would do it. I suspect we’d be wiser, or we’d be dead.