Sorry, but people don't file a lawsuit "every time" there is an accidental death--our courts would be hopelessly clogged with thousands more lawsuits if that were the case. The reason it may seem that way is simply because accidental deaths generally become newsworthy only when a lawsuit is filed. (Note also there were almost 200 snorkeling deaths in Hawaii over the past decade or so according to the study--this appears to be the first lawsuit filed over one--at least no others have been referenced.)
Would be interested to see the complaint filed in this suit and learn more of the facts, but certainly understand why one was filed. We would probably never have heard of this incident without the lawsuit, so it has already had a postive effect in informing me, and apparently many others here, of a risk I was not previously aware of.
Moreover, it seems Hawaii authorities might have been dragging their feet in warning about this--they commissioned a study that in 2022 recommended additional warnings, especially relating to snorkeling after air travel, but then did nothing. The study showed a MUCH greater incidence of deaths from snorkeling for non-residents (vs. residents) than any other aquatic activity (including swimming), which surely was a red flag. (Note that Egyptian authorities had already warned of using full-face snorkel masks in 2020 according to a previous scuba board thread (though we don't know if one was used in this case).) And the coroner didn't help by misleadingly describing the cause of death as "drowning."