I've often wondered if it would be possible to design a source control system that could track this lineage. Kind of like, "inside" of a commit would be a hidden history that you could unpack if you wanted to. "This single commit is actually the squash of these other commits made by this guy". "This commit is actually the rebase onto mainline of this commit a guy made when his machine was behind". The commit would look like normal to the current source control CLI, by default, but would reveal this hidden level of detail if you inquired "How was this commit made?" - then you'd get the reflog.

I've wondered if support for a feature like this could finally resolve the "debate" between merging and rebase. The people who like having the full history (whatever that means) would have it, and the people who care about logical changes would see it by default. The cost would be that the repo history would indeed have the full level of detail, but you could imagine supporting a cleanup operation that erases this "origin" information for commits that are sufficiently old, or else simply doesn't pull the info by default and fetches it only when necessary.

(You can kind of simulate this using merge commits, by only looking at one parent, but it doesn't really work out well in practice.)