Why spend the cost on dual X and Y when you can failover to another cluster?
For big DC workloads, it is usually, though not always, better to take the higher failure rate than add redundancy.
For big DC workloads, it is usually, though not always, better to take the higher failure rate than add redundancy.
Actually, now that I type that it makes sense. Scaling a few tens of dollars to a bajillion servers on the off-chance that you get an inbound power failure (quite rare I'd reckon) might cost more than what they'd lose if it does actually fail.
So yeah, they're potentially just balancing the risk here and minimising cost on the hardware.
Edit: changed grammar a bit.
More modular and a lot less copper at 10x the voltage. Still a lot of copper.