Though with a sufficiently-gnarly release history, even the Git repo might not tell the full story. I've recently been tracing the history of one particular library that's been around since the early 2000s, and hardly any of the versioned Git tags correspond exactly to the files in the released tarballs. Finding all the releases was quite tedious: the tarballs were published on multiple websites, some tarballs were updated in place (without changing the version number), one website (which held some versions exclusive to it) routinely deleted very old versions, and that website also no longer exists outside the Internet Archive. Overall, some of the releases have been totally lost to time, and the Git repo is of no help in reconstructing them.