Yep, because of the misuse-worst-case arguments. Simple solutions that guard against such mistakes are welcome. E.g. we could allow squashing if all commits' commit messages except the first one's start with "[SQUASH] " or "fixup! ".
Because it is meant to be the default, doing only when some specific message exist is not going to fly. Using !donotsquash or alike in the commit message is, however, a good way to proceed.
