The system shares some blame, but the individual is also the one exploiting a confluence of factors. Should the system prevent one person from purchasing 40% of global RAM production with fake money, yes, it should. But our systems are glacial to respond to edge cases they were not prepared for, and this is an extreme edge case - people who are not Sam Altman could not pull off purchasing 40% of the world's RAM production capacity on an IOU. Only a very few individuals in the world could have exploited this gap in the system, and the one who actually did deserves blame for it.