The gamifying started immediately.
If you ever make anything competitive there will be that one guy trying to cheat his way to the top.
The high score list was supposed to be for finding logic errors. This guy was trying to pass off finding typos in text strings as equivalent to finding something that would blow up prod if pushed up.
I really... hate... reality
I would have thought that software engineers, of all people, would understand that one's intention and what they actually implemented in a system can be two different things, and careful effort must be expended to properly implement it, and that "good intentions" alone is not sufficient.
In order for a game like this (what you described is a type of game) to work, all players need to have the same level of trust vectors toward the other players. This type of situation only emerges in very localized instances. The military, for example.
But more seriously, while this is worded as a result of abuse, it had been up for more than a year at this point as a way to push people to use Kiro (you get badges for each "level" basically). Once you reach a point where everyone is using those tools, it makes no sense to keep it around.
Also it was not related to any performance metric, it was a pure vanity thing of getting virtual awards to display.
Frivolous usage sure, internally at Amazon there is a subculture (if you can call it that) of award chasers. Using Kiro for mundane task to burn tokens does not sound that far-fetched.
Overall usage though no I don't think so, these tools have some pretty wide adoption at this point and not by people chasing awards.
They are so smart. Great job all.