What is Reddit's opinion of Freebsd Mastery: Advanced Zfs?

From 3.5 billion Reddit comments

If you're talking about pulling 1 drive and reading the content fully on that one particular drive, then no RAID/btrfs soft-raid/mdadm/ZFS/hardware RAID is going to provide that unless you do a RAID 1 on a compatible system.

If you want cross platform (BSD/Linux), the answer is soft RAID with ZFS, that will work anywhere and require the least spending in hardware to make operational and have a decent featureset.

With that all said, no RAID of any kind is a backup, hard drives are mechanical devices and flash chips wear down, they will eventually die in some form or another. If you want a backup, then you need three copies of your data, one, the original, two, the local backup storage, three, off site in a non mountable fashion.

Anyway, I do want to point out the way you started this topic was in a bashing manner along with showing how little time you've put into the research of ZFS. There are books that can teach you fundamentals like https://www.amazon.com/FreeBSD-Mastery-Advanced-ZFS/dp/0692688684 and https://www.amazon.com/FreeBSD-Mastery-ZFS-7/dp/0692452354 if you like reading.