A new option virt-v2v -io vddk-noextents=true was added in RHEL-88863 (9.7) and RHEL-88864 (10.1).

However it did not turn out to be effective at improving performance, could not be used by MTV, and has been superseded by a better change in nbdkit (RHEL-94825).

I have also removed the option upstream: https://github.com/libguestfs/virt-v2v/pull/93

Therefore we should revert this change and remove the feature.