That's interesting. Perhaps the fact that I've learned about ops entirely in the era of virtual machines running atop disposable, generic, and (in the case of AWS) entirely invisible hardware has distorted my thinking on this matter...
"Sysadmins and devs shouldn't really care if they have five generations of hardware."
I wish it was true. sadly there are some services where scale and latency is so carefully measured that individual software releases are rejected if performance gets worse (or unacceptably worse, etc). In these situations you need to test on all hardware platforms. It is much better to have fewer platforms: Optimally: the one you are migrating off of, the one you are moving to.
For desktops... have you ever tried to maintain an Windows or Linux desktop environment with more than 4 "standard desktop configurations"? It becomes a nightmare. If you have a single "gold image" you blast to all machines it makes the task harder; if you stay with the vendor's OS and try to maintain it "forever" it is even worse.
One thing that makes virtualization a "win" is that the virtual box looks like a single hardware platform. It reduces testing, etc. However, then you still need to test the virtualization software on all hardware platforms... so you've made things easier for everyone but that team.
