Admittedly, times change and sometimes manufacturers surprise us with relatively reliable products from time-to-time. As a PC builder/repair guy it behooves me to say that my experience with Western Digital mechanical hard drives has been considerably less than pristine. More than 80% of the PCs brought to me by people encountering irreparable hard drive issues were using Western Digital mechanical drives. I don't know if this is an "only in Canada" thing or if it extends to the rest of the globe. Yes, I've seen my share of bad Seagate drives as well (especially those slim 500GB drives) but more commonly it's a WD drive that has cratered. Brand names aside CMR (conventional magnetic recording) hard drives seem to be able to take more abuse than SMR (shingled magnetic recording) hard drives. So for those who insist on purchasing mechanical drives from Western Digital I highly recommend making sure that they are CMR hard drives. This applies to external USB type drives as well.
Once upon a time there was an issue with external drives over 3TB keeping their partitions unless they had a FAT32 boot sector and the user avoided formatting them to GPT. This issue was not limited to Western Digital external drives. Perhaps that was the deal with this 5TB drive. Ultimately, I can only speak from personal experience on this and I believe most of my external drives are now GPT. This does not appear to be an issue anymore although it might still be with older systems than what I use. Perhaps someone else here might know.
FAT32 still has its uses. It is needed for flash drives, SD cards, utility drives, and it is a favourite among those who do PC repair. I still use it to flash BIOS, for example. I imagine it will still be around for some time.