Why did someone bump this thing?
Still with that said I'll throw in my two cents on this. As a professional lifesaver, it is always better practice to make preventative measures. In the ocean, I make contact with people in rip currents before they are rescues. Often the rip opens up so fast that by the time I get to them people have already begun struggling. It's not good policy to rely on a person's ability to struggle for survival (especially in the case on non-swimmers), but often we are forced to do it. In one incident, which was documented on the tv show Ocean Force, a fellow guard at my beach was already in the water pulling three people in on his buoy, while his two flanking towers were also responding to rescues in their water. A non swimmer and his friends entered the water and were sucked into a rip current. His friends got out. I pulled their buddy off the bottom an hour later. Normally, the trucks, and boat have personnel to respond, but this all happened before we got there. If the kid knew how to swim, we could have reached him while he struggled.
I have been in these wave pools with swimmers and innertubes and I remember having my son (who happened to be four at the time) with me. He wasn't big enough to fit in the innertube and he kept falling through the hole. When the waves fired up it was a nightmare.
There were WAY too many people in the pool and with all the innertubes it created some very dangerous spaces. I literally rescued my own son and muscled us out of there. The lifeguards at this particular waterslide park sucked. They were just kids that knew basic CPR and could swim well enough to pass a few tests. They were not scanning the water, and were not on top of the situation. When I got us out of the water I went and complained to them. I told them that they've got a very dangerous situation on their hands and that someone is going to drown. I got eyerolls and was blown off. I complained to their supervisor. Same thing. I've never returned to that park.
So I can understand the environment that caused this childs death. I also understand it way better than most people. Still, I would have never let my four year old go swimming in that pool without me. Maybe I would have stood by if there were no innertubes, but he would never be far from my reach.
So I say, the lifeguards suck, the environment created with those innertubes sucks, and the mom sucks for not staying by her child.