Realistically, the universe is very unlikely to operate under the scenario that series depicts, because if an alien species existed with sufficient technology to wipe out other intelligent species from a distance, and desired to take out any other species they knew about like the whole dark forest idea implies, then they shouldnt need active proof of intelligence like an attempt at communication, it should be simpler to just look at planets for signs of planetary biospheres, in their atmospheres for example, and launch whatever planet-sterilizing weapons they planned to use at lifebearing planets before anything intelligent ever evolves. If they get powerful enough (which given the age of the universe they probably should be, it would seem fairly unlikely for all spacefairing aliens in a given area of space to have come about within even the same million years, even if sci-fi likes to portray it this way) then they dont even need to look for biosignatures, they could just preemptively attack every planet in the galaxy with relativistic projectiles. There are a lot of planets, sure, but a finite amount, and they’d have a lot of time to do this in. Hiding should be essentially impossible, because your location is almost certainly compromised before you even exist. Given that we exist, this implies that nobody in this general side of the galaxy behaves this way, either because there are no species in this region with the capacity to do this, or because they do not behave in such a hostile manner. Further, a species that does have the capacity to operate this way should at least consider that, if other intelligent species exist with any frequency, then it is very unlikely that they are the first intelligent species to exist, and therefore that as their territory or general area of contact and influence expands, they will inevitably encounter some civilization more powerful than theirs. When they do encounter that more advanced civilization, then having a history of destroying every intelligent species they find immediately is not going to give them a very good impression, and probably would get them seen as a threat, far more than they would if they were not overtly hostile to everything they encounter.
Realistically, the universe is very unlikely to operate under the scenario that series depicts, because if an alien species existed with sufficient technology to wipe out other intelligent species from a distance, and desired to take out any other species they knew about like the whole dark forest idea implies, then they shouldnt need active proof of intelligence like an attempt at communication, it should be simpler to just look at planets for signs of planetary biospheres, in their atmospheres for example, and launch whatever planet-sterilizing weapons they planned to use at lifebearing planets before anything intelligent ever evolves. If they get powerful enough (which given the age of the universe they probably should be, it would seem fairly unlikely for all spacefairing aliens in a given area of space to have come about within even the same million years, even if sci-fi likes to portray it this way) then they dont even need to look for biosignatures, they could just preemptively attack every planet in the galaxy with relativistic projectiles. There are a lot of planets, sure, but a finite amount, and they’d have a lot of time to do this in. Hiding should be essentially impossible, because your location is almost certainly compromised before you even exist. Given that we exist, this implies that nobody in this general side of the galaxy behaves this way, either because there are no species in this region with the capacity to do this, or because they do not behave in such a hostile manner. Further, a species that does have the capacity to operate this way should at least consider that, if other intelligent species exist with any frequency, then it is very unlikely that they are the first intelligent species to exist, and therefore that as their territory or general area of contact and influence expands, they will inevitably encounter some civilization more powerful than theirs. When they do encounter that more advanced civilization, then having a history of destroying every intelligent species they find immediately is not going to give them a very good impression, and probably would get them seen as a threat, far more than they would if they were not overtly hostile to everything they encounter.