>>1314443598% of stars in the universe that could form are already formed or even already died.
The sun is a third generation star.
The Galactic Federation of Planets is very old in peace since a long time
various species of aliens are monitoring Earth since millennia, since they discovered a sapient species here, we are the North Sentinel Island of the Milk Way.
The discovery of radio signals and nuclear explosion (with in-site sensors, not from another star system...) attracted their attention more and more species arrived.
The encounters until now are just accidents, because the federation is like the EU, a benevolent but messy agglomeration of very different people and a bit uncoordinated, in a comically way. Imagine the EU forces in the movie No Man's Land (2001). Only a few are trained soldiers, but that's for general security.
They probably have small bases and communities on Earth and such, but life gets boring for the long wait for anyone, so they go around the hood like you will do with your car, especially youngsters of the families of the bases.
They will make contact either the day we discover ftl propulsion or ftl communication or reach world peace or just before we completely destroy the global ecosystem (so in 20-50 years max for the last one). This is because we are still uncivilized, they don't want a cargo cult or the metaphorical local thugs at their peaceful neighborhood park. Until then, their general rule is avoid interactions, stay hidden and don't fuck up.
this is my take.
