All this guff about peaceful aliens misses the point - I think this is more like Pascal's wager.
Consider the cases where we hide:
"If aliens exist and are very nasty, I'm sure glad I didn't broadcast our existence to them"
"If aliens exist and are super peaceful and awesome, well, nothing bad happened because we didn't broadcast our existence to them".
Consider the opposite cases:
"Aliens are nasty and we told them we existed - now we are all dead"
"Aliens are super awesome, we told them about us and they didn't wipe us out, possibly doing something good for us".
No matter how good the potential benefits from "nice aliens" you are a fool to stake the future of the entire human race on what is essentially a gamble when you don't have to.
Consider the cases where we hide:
"If aliens exist and are very nasty, I'm sure glad I didn't broadcast our existence to them"
"If aliens exist and are super peaceful and awesome, well, nothing bad happened because we didn't broadcast our existence to them".
Consider the opposite cases:
"Aliens are nasty and we told them we existed - now we are all dead"
"Aliens are super awesome, we told them about us and they didn't wipe us out, possibly doing something good for us".
No matter how good the potential benefits from "nice aliens" you are a fool to stake the future of the entire human race on what is essentially a gamble when you don't have to.