Sometimes the first opportunity to see something occurs while you are actively destroying the habitat where it lives. Sounds like your friend's work took advantage of the access that deep sea trawlers would have to species unknown to science, allowing them to have a rough idea of their distribution. In a sense this is very useful to researchers who can argue the case that trawling is too destructive for that area due to the presence of species new to science.
Trawling and mining, both activities mentioned in the article, can be very destructive to habitats. With the global race to lock up sources of rare elements and elements that are more commonly found in conflict zone nations the sea floor is seen as the best source for some of these. The manganese nodules that I learned about in geoscience classes decades ago are targeted by miners today who will have no qualms about scraping the seafloor clean just as those fishing fleets strip the oceans of wild fish species.
No one is mining manganese from the sea floor. The whole idea was a CIA cover story for a mission to recover a sunken Soviet submarine that the Americans knew the location of but the Soviets didn't. They needed an explanation for a cargo ship headed out to a specific area with deep sea construction equipment on board: https://en.wikipedia.org/wiki/Project_Azorian
> The manganese nodules that I learned about in geoscience classes decades ago are targeted by miners today who will have no qualms about scraping the seafloor clean
This (and the concept of extinction credits) is an opening plot point in the book “Venomous Lumpsucker”, which I found a good read.