Any science fiction writer or fan worth their salt knows what Fermi's Paradox is.
If there are alien civilizations out there, why haven't they contacted us?
I've thought of many reasons over the years, including the difficulty and expense of interstellar travel (if faster than light isn't possible, then it's a very long...although far from impossible...trip).
Here's another thought.
One of the reasons commonly cited is that truly advanced civilizations would have a Prime Directive. This is generally mocked by most people who don't support it as 'why would they do that?'
Well, hear me out.
A civilization advanced enough to have interstellar travel is not going to be flying around the galaxy for resources or even finished goods. We're on the verge of having Star Trek style replicators ourselves. The only thing a starship might want from another system is fuel.
So, what IS worth trading between the stars?
Except that a truly advanced civilization isn't going to get meaningful scientific information from one that's lower in development.
What kind of information, then?
Intangibles. Things that will be different from system to system, species to species. Things affected by who we are and what our sensory capabilities are.
What does this have to do with the concept of the Prime Directive?
If you contact an insecure or unstable race, their culture will be irrevocably damaged. And what will be damaged will be those very intangibles that are the only things worth trading with them for. As the newly contacted species learns from you, there is a very real risk that they will trade their culture for yours...ruining their value as trading partners.
It is only worth trading with a mature species. Therefore, guidelines against premature contact would be in place to ensure that a species becomes 'mature' before they are contacted formally. (Informally might be another matter...but there's all kinds of stories there).