alt Hacker Newsthey aren't being specially punished. they are being made to follow the rules that quickly to every other company that IPOs. These rules aren't arbitrary. They exist because without them, retirement accounts would be vulnerable to companies doing all sorts of nonsense to manipulate the indexes.
That might be a valid motivation for keeping the rule, but as far I can tell it can't be the original reason for this rule as it predates passive indices in retirement accounts being that popular.