[cgbg]

The very fact that Earthlings ARE sending such signals means that NASA et al have already decided that this situation is worth the risk.

If I were an alien race (with no hostile intentions) I would conclude humans are dumb as rocks (for making that insane reward/risk assessment) and are not worth the trouble of contacting.

I would be looking for intelligent civilizations--they would have created technology to camouflage their presence from possible hostile outsiders.

[PIF]

Any civilization not worth contacting is worth eliminating: resource consumption plus a breakthrough could happen at any time changing the balance. Strike while they are stupid, blind and powerless.

If a civilization is intelligent enough to create camouflage masking its existence, you would not find it before it found you. Just the act of searching would reveal your existence which is why navy ships use passive radar and sonar.