I admit the way they are going to go about it is an ecological disaster. There is no need to do it this way but they just can't get their heads around using the sea as a friend and not an enemy and also they don't listen.
They can estimate anything they like. Reality is that nobody has Ever successfully operated at these depths. The CCZ is 4,000m to 6,000m. Nodule density varies from tightly packed to one every square meter.
All the rahrahrah statements are fine but until the moment they actually start mining in earnest, this is all aspiration.
Hence I'm not going to cry "ecological disaster" until they prove they can actually create one. Yes I get they are saying they are going full ahead to do this. But what they are saying and what they are doing are two different things.