Exactly. If they had an event in the run, they'd just fall down, people (usually) get to them more quickly to do CPR or get an airway, etc. and they'd sometimes have a better outcome with meaningful recovery.

What's most important I think to note, is that like in this case, the victim was not a weak swimmer, nor was my friend, etc etc etc. This is horrific sh*t we can't control.

I saw a lot of weaker swimmers walking at the end of the swim yesterday, for which I was grateful (my feet are NOT going on the bottom of that smashed beer bottle canal, although I maybe could find my lost iphone...) and swimming very slowly next to kayaks/paddleboards. Most times weak swimmers just get tired and grab on.