I would argue either RAID 5 or ZFS RAIDz1 are inherently unsafe, since recovery would take a lot of read-write operations, and you better pray every one of 4 remaining drives will hold up well even after one clearly failed.

I’ve witnessed many people losing their data this way, even among prominent tech folks (looking at you, LTT).

RAID6/ZFS RAIDz2 is the way. Yes, you’re gonna lose quite a bit more space (leaving 24TB vs 32TB), but added reliability and peace of mind are priceless.

(And, in any case, make backups for anything critical! RAID is not a backup!)