Good point, this system is much more useful for scientists and ML researchers, etc. wherein the code may generate datasets over several weeks or months of compu

Good point, this system is much more useful for scientists and ML researchers, etc. wherein the code may generate datasets over several weeks or months of compute time, but produce some output that should be directly tied to the code. You're right though. Systems in the social media space dealing with users appending to a database typically don't have this requirement to be easily reproducible, so the local snapshots are the right choice.