It's not just the location of the active beacon that you're giving away. It also tells the enemy in which regions of the world's oceans you are listening.
If you cover the entire ocean than that is not an issue.
But meanwhile I think I figured out that such an array would be a major issue because once the locations of the beacons is known, they will effectively turn every passive sonar into active sonar. Therefore it can not provide an asymmetrical informational advantage even if the investment would be asymmetrical.
I was not asking about feasibility or externalities. I do not consider it a good idea. I was just asking about military usefulness. And as I said, after reflecting, I suspect even from that POV it would be detrimental.
But meanwhile I think I figured out that such an array would be a major issue because once the locations of the beacons is known, they will effectively turn every passive sonar into active sonar. Therefore it can not provide an asymmetrical informational advantage even if the investment would be asymmetrical.