The split among archosaurs between what would go on to become crocodilians and what would go on to become birds happened a long time before there were dinosaurs

The split among archosaurs between what would go on to become crocodilians and what would go on to become birds happened a long time before there were dinosaurs. Yes, crocodilians are the closest living non-bird relatives of birds, but they're not all that close as these things go.