Before someone uses Google's servers as an example, I would say that strapping together consumer grade components with zip ties and no case isn't what I'd consider a 'server'; rather, a loose collection of parts.
Google has 3 orders of magnitude more servers than I’ll ever need. With that sort of difference it’s not only a change of solution but also a change of rules.
My sense is that storage server prices have had to come down to compete with both cloud (like S3 archival tiers) and roll-your-own solutions. The former are relatively recent and the latter have become more feasible as companies—Backblaze among them—have open sourced well-engineered designs. Storage server margin used to be insane, over 80% after COGS back in the 00s and only slightly less last decade, and there's still room to compete.
I hope history will eventually read something like this:
In the aftermath of the Dot Com Bust, manufacturers became conservative, and lost their ability to dream big. Into this power vacuum stepped the so called Cloud Providers, who in some cases made their own hardware and tools to solve their problems.
Over time manufacturing caught up, missing tools were written, and the Cloud providers went back to solving the main problem nearly none of their customers of suppliers could ever solve: the speed of light (locality).
> Over the last few years, we began using storage servers from Dell and, more recently, Supermicro, as they have proven to be economically and operationally viable in our environment.
They may have just reached a scale where it was viable, where it wasn't before. The bigger you are, the bigger discounts you can negotiate. They also certainly have the leverage to walk away from a deal, since they have proof "hey, we'll just build our own if we don't like your offer."
I would imagine that in the early days there was nothing that met the requirements. Early on very few systems had the drive density needed - products like Sun's Thumper with 48 drives (https://en.wikipedia.org/wiki/Sun_Fire_X4500) were few and far between.
Today there are lots of high storage density devices, so no point to build your own if you can get it already engineered and with a warranty from somewhere else.
