FR: make git clone --depth and --shallow-since produce maximal set of commits

Problem: "git clone --shallow-since 2022-12-01 --depth 1" recently
failed with "fatal: the remote end hung up unexpectedly" because the
repo happened to not have any sufficiently recent commits.  I was
hoping that by also specifying "--depth 1" that I would get at least
one commit, but it seems combining these options produces an
intersection of the available commits (in my case, zero).

Obviously I can work around this but,

Proposed change: It would be useful if we changed the behavior of
these flags specified together to produce a union of commits instead
of an intersection.

I doubt there's a lot of prior art use cases depending on the old
behavior.  What do you think?

Thanks!  - Jonathan.