"Due to potential legal incompatibilities between the CDDL and GPL, despite both being OSI-approved free software licenses which comply with DFSG, ZFS development is not supported by the Linux kernel"
AIUI, ZFS really requires multiple drives to be effective.
You might gain a little value from extra checksums on file system blocks on a single drive, but if those checksums ever start failing on a hard drive there is a high likelihood that most of the drive is about to fail completely.
I had researched ZFS a fair bit as I planned to build my own FreeBSD NAS around 3-4 drives in ZFS, but eventually decided to buy an off-the-shelf ZFS NAS from the TrueNAS people.
@mcc in btrfs - every file can have different compression, if you're crazy enough. What I do is set compression on the root folder of a new fs, and let that be inherited everywhere.
btrfs property set . compression zstd:8 ; chattr +c .