Libcryptsetup lacks API providing (safe) dafault encryption parameters for reencryption (all modes) or luksFormat actions. The CLI provides defaults but there couple users of libcryptsetup that would make good use of the API.

Libblockdev (vtrefny@redhat.com) and, I guess also Stratis project, would make good use of the API. Any future change in default encryption parameters would affect libcryptsetup users.

Also, there are different default for ordinary installations and RHEL instalations in FIPS mode. Eventual new future "profiles" might be added (embedded devices, RHEL on ARM devices, etc.).