Saltwater corrodes firefighting equipment and may harm ecosystems, especially those like the chaparral shrublands around Los Angeles that aren’t normally exposed to seawater. Gardeners know that small amounts of salt – added, say, as fertilizer – does not harm plants, but excessive salts can stress and kill plants.
I mean, salt was expensive as fuck, people weren’t wasting it to fuck over someone very far away…
Most of the time it was a symbolic gesture with like a hand full of salt.
Dumping sea water at this volume tho will have an effect for a long time, and we can’t really undo the damage. Which is why it’s an apt reference.