Commercial fishing is overfishing the seas, they're taking many more species than they sell through drift-netting and similar "catchall" techniques. The dead overkill is just dumped back into the oceans. Whole ecosystems are collapsing.
A lot of attention has been given to plastics in the ocean, but discarded fishing nets are a much bigger problem.
Yeah, the narrative is not new. And the filmmakers don't bring any particular insight or context to the discussion. Their rather naive recommendation is that people should eat less seafood.
The solutions don't match the problem. We're all fucked through any number of ecological disasters we are calling down on ourselves.