Only if you considered the purpose of power-saving mode to reduce total energy usage, vs to reduce amount of power (and consequent wear & tear) an individual machine uses. However that MS would release a feature like that which automatically kicks in on upgrade without any sort of consideration of what the machine was used for - it could be running life-support systems! - seems an issue. But I'd also expect a fair bit more diligence on behalf of engineers responsible for monitoring and maintaining systems that need 24x7 uptime.
i shudder at the thought that a critical piece of life-support anything would be running a windows based OS.
Life support systems don't run windows. And if you're running consumer windows on anything critical, you fucked up.