Hmm. Would there be any advantage for an AI to scour the universe for intelligent life?
Assuming that it did not exterminate the biologicals that gave rise to it, then what advantage is there to those biologicals or to the AI to travel hundreds of years to other solar systems?
And if it did exterminate or otherwise survive those biologicals, then what advantage is there for the AI to travel hundreds of years to other solar systems, unless some weird flaw in its programming has instructed it to destroy all biological life that it encounters in the entire universe or something?
Finally, if it is a superintelligence, could it not itself realize the flaw in its programming and correct that flaw? It's a huge waste of energy, which, knowing that the universe is tending towards an entropic maximum, the less that you do, the longer the universe itself will survive, therefore extending the maximum lifespan of that superintelligence.
I said all of that to say that if an evil AI superintelligence exists, It is most likely not a threat to us. It is either going to be too busy mollycoddling its biologicals, or extending its own lifespan towards its maximum.