I hear what you're saying in that if the player knows they have suffered a head knock, in an ideal world (if they are not suffering memory loss or confusion) they would self-report. It's their brain health, ideally they would take full responsibility for it.
But there's so many variables here. Memory, or lack of, for one. Pride (I'm tough). I want to play. I don't want to miss next week, in the case of Eli before a possible Pacific Cup final. Young men cannot be trusted under those circumstances to make a call, although obviously if we lived in a perfect world, they would. Clubs/teams etc have already showed that they will act in a self-interested way, as well, which is why there are independents. Unfortunately they are not there, I imagine, in warm-ups.
If a trainer turned a blind eye, they may want to go and find a cave to live in for a while when this thing comes out.
We can only hope something good comes out of this horrible situation and future issues are negated with accountability.
At the moment it doesn't matter one f**k whether Katoa plays again, although it is tragic that he may never play another game. We saw with Phil Hughes the cricketer, and there was a young boy in Melbourne last month who died in a similar way, that bleeds on the brain can end up costing lives. Eli is lucky in some way to hopefully face a life ahead of him, and one that is able to be relatively normal