Alex Henrie [off-list ref] writes:

Name the new option "drop" intead of "no" or "false" to avoid confusion

This is traditionally called "flattening the history".  Don't we
confuse uesrs by introducing a new phrase?

rebase-merges is about transplanting the history without flattening,
i.e. keeping the mergy commit graph topology.  If there are only two
kinds of rebase (i.e. keeping the topology which is rebase-merges
and the other "flattening" kind) operation, shouldn't the option be
called "--no-rebase-merges" instead?  --rebase-merges=no is also
understandable.

in the future if --rebase-merges grows the ability to truly "rebase"
merge commits by reusing the conflict resolution information from the
original merge commit, and we want to add an option to ignore the
conflict resolution information.

I am not sure why such a change "in the future" is not merely a
bugfix of the current "--rebase-merges", though.  Once it is fixed,
is there a reason to make the fixed behaviour only available behind
an option?