I think that's debatable. Many open source licenses have a definition of accessible source code that is similar to:
> The "source code" for a work means the preferred form of the work
for making modifications to it.
Certainly, in the past "a tarball of the source for whatever version you have" was absolutely considered sufficient for that. But these days the features provided by source control systems, such as "annotate"(/"blame"), "bisect", etc... could very well be argued to have raised the baseline for what "the preferred form of the work for making modifications to it" should mean.
I think that's debatable. Many open source licenses have a definition of accessible source code that is similar to:
> The "source code" for a work means the preferred form of the work for making modifications to it.
Certainly, in the past "a tarball of the source for whatever version you have" was absolutely considered sufficient for that. But these days the features provided by source control systems, such as "annotate"(/"blame"), "bisect", etc... could very well be argued to have raised the baseline for what "the preferred form of the work for making modifications to it" should mean.