Indeed, the Fediverse operates on the premise of public visibility, allowing users to share their thoughts and content with a broad audience. It's more about publicity than privacy.

However, the concerns about privacy in the Fediverse arise not from the act of sharing content itself, but rather from the potential risks associated with sharing personal information unintentionally or without proper consent. While people are aware that their posts are public, there can still be instances where sensitive data is inadvertently exposed, leading to unintended consequences.

Moreover, the issue isn't limited to the immediate act of posting but extends to the longevity and persistence of data. Information shared on the Fediverse may persist on various servers, and as you pointed out, circumstances or perspectives might change over time. Ensuring that users have control over their data, even after many years, is a crucial aspect of privacy protection.

The intent is not to stifle free expression or prevent people from sharing their thoughts openly. Rather, it's about empowering users to maintain control over their data and make informed decisions about what they share, with whom, and for how long. Striking a balance between publicity and privacy is essential in fostering a healthy and respectful online environment.