There could be billions of intelligent civilizations in the visible universe, and we could still be effectively alone, given there are hundreds of billions of g

There could be billions of intelligent civilizations in the visible universe, and we could still be effectively alone, given there are hundreds of billions of galaxies. The Grabby Alien solution argues that we're still early for such civilizations, because otherwise the grabby ones would have expanded and taken up all the real estate. Since we see no evidence for that, we must have arisen early while there's still plenty of available space (they can still be out there, just very far away).