Heck, I’m sitting here at a computer and have a serrated Spyderco Delica clipped in my pocket, as I do most of the time (98%+) I’m not dressed for bed. I can’t imagine not having one at hand. Maybe it happened too fast, and he was taken down to depth very quickly, such that a knife didn’t matter?
In any case, some added buoyancy from a life vest, a knife, and some quick thinking would have likely led to a favorable outcome here.
I wonder if he was alone.
We don’t have any details at this point.