ZFS has the notion of version numbers - for both the zpool and filesystem. The last FOSS releases are zpool 28 and zfs 5. There have been subsequent releases of ZFS by Oracle, but versions 28 and 5 are the latest used by all the open source implementations.

What the FOSS community has done is to add "feature flags" to ZFS instead of constantly bumping the version number. So encryption is a feature on top of zfs, but the encryption introduced in FreeNAS for ZFS isn't the same as the encryption in Oracle's zpool v30.