I have seen homogeneity 'kill' twice in my career. The first time was unprovisioned hardware, then second time we lost half of the hard drives assigned for dev machines in the space of about 9 weeks. I had so many processes in place by that point that it was a huge inconvenience (mostly due to whole disk encryption) but zero data loss.

The worst thing you can do is to put all of your eggs into one basket. And bulk ordering might get you a set of drives all from the same batch. Bad batches will tend to all fail for a similar reason. Drives fail on a bell curve, right? So the first drive may fail way before any others, but in a RAID array, rebuilds are stressful. Eventually you will hit a statistical cluster. Multiple drives failing close together. If that happens during a rebuild, you will lose a RAID 5 array. If you are very lucky, your RAID 10 array loses two drives in the same mirror. If you have two failures during a long rebuild, even RAID 6 won't save you.

I just bought a Synology box for home. This is my third and probably final RAID enclosure for personal use. I was having trouble finding Backblaze-tested drive models to populate it, so I filled it with drives from a Drobo and kept looking. Initially I had populated the Drobo with 4 drives I bought at once. When one failed, I bought 2 HGST drives and replaced a pair. When the new drives arrived, I started trying to cycle them through, and one of the drobo drives failed. I'll give you two guesses which one.

There is, as far as I can tell, no prosumer multi-disk filesystem that uses consistent hashing to stripe+mirror files across an arbitrary number of disks, instead of the heavy linear algebra RAID5 relies on. It requires touching the whole disk on every rebuild, and I believe that's why Object Storage is slowly taking over from the top end. It's a simpler form of redundancy.

I hope that it's worked its way down to my price range by the time the motherboard on the Synology burns out.