Yes far worse as the seabed is destroyed over vast areas, as opposed to the small footprint of an oil rig, as the extraction method is to scrape off the surface of the seabed, as that is where the cadmium is.
Unfortunately that is where the life is, in the top 1 metre.
It is being trialled as we speak.
It is just moving the problem elsewhere & is already being said that it will be the next global ecological disaster.
New power stations outputs will be greatly offset by existing stations being shut down.
I am no eco warrior by any stretch of the imagination but there is a massive lack of forward planning going on, as usual.