Like, 25+ years ago I would've bought hard drives for just my personal usage in a software raid making sure I don't get consecutive serial numbers, but ones that are very different. I'd go to my local hardware shop and ask them specifically for that. They'd show me the drives / serial numbers before I ever even bought them for real.
I even used different manufacturers at some point when they didn't have non consecutive serials. I lost some storage because the drives weren't exactly the same size even though the advertized size matched, but better than having the RAID and extra cost be for nothing.
I can't fathom how anyone that is running drives in actual production wouldn't have been doing that.
I mostly just buy multiple brands from multiple vendors. And size the partitions for mdadm a bit smaller.
But even the same model where it's 2 each from bestbuy, Amazon, newegg, microcenter, seems to get me a nice assortment of variety.
Of course, learned experience has value in the long term for a reason.
I rescued what could be rescued at a few KB/s read speed and then checked the serial numbers...
I just get 1/3 Toshiba, 1/3 WD, 1/3 Seagate.
Moving to software storage systems (ZFS, StorageSpaces, etc.) has saved my butt so many times.
I'll toss in on that anecdata. This has happened to me a several times. In all these cases we were dealing with drives with more or less sequential serial numbers. In two instances they were just cache drives for our CDN nodes. Not a big deal, but I sure kept the remote hands busy those weeks trying to keep enough nodes online. In a prior job, it was our primary storage array. You'd think that RAID6+hot spare would be pretty robust, but 3 near simultaneous drive failures made a mockery of that. That was a bad day. The hot spare starting doing its thing with the first failure, and if it had finished rebuilding before the subsequent failures, we'd have been ok, but alas.