The S&P has decided not to change its rules to allow for faster entry of mega IPOs, such as SpaceX, into its index. This decision comes after some other indices, like the NASDAQ 100, have already made similar changes. The discussion around this topic has been marked by misinformation and alarmism, with some commenters expressing concerns about the potential impact on retirement funds and the stability of the market. The S&P's decision is seen as a way to maintain stability and avoid potential risks.