I wonder what would be the impact of any mining operations on deep sea wildlife. The article doesn't seem to discuss this.
The main governing body for this type of work is the international seabed authority: https://en.m.wikipedia.org/wiki/International_Seabed_Authori...
A hot area they have looked at is the longing of poly metallic nodules: http://www.eu-midas.net/science/nodules
While no one has actually started mining operations yet, they are working in that direction, trying to get ahead of the environmental impacts first and foremost.
While there is a strong argument for “protecting” the environment, I don’t see that as a justification in it if itself to not do resource extraction. While not perfect, they seem to be heading toward a conservative approach to mining. In it (at least last I heard) they are deliberately setting aside large swaths of areas with the valuable resource as “wildlife reserves” similar to what we do in the United States, and Australia is going for the Great Barrier Reef.
I don’t know the future here, but there are too many people in this planet clamoring for resources not to look at all options (though personally I would prefer to enable space mining).
Or have been pressured into silence.
There's no argument that environment impact needs to be evaluated--that's just not what these particular people are qualified to assess. It's unlikely that the entirety of academia will avoid discussing the potential consequences of these ideas. Those who are qualified to do so will.