> Luckily I found an old local copy of my project, but this taught me not to rely on Github as only storage for code.

This is the distillation. If something matters to you, you should personally take responsibility for its long-term storage. Apparently for the author, finding a true duplicate was just luck. To minimize the risk, maintain multiple copies on multiple media. Github is only one medium.

The context is especially notable: this is source code and source code is (in a majority of cases) very small. Maintaining personal archives of project source is a comparatively simple and low-cost matter.