You just plain aren't going to do that in an hour when you're offline because someone trashed your automated systems - resetting and restoring the grid would require people on site, in communication. That's not happening in an hour without staggering expense.
So at the top, all the leaders are just trolling the populace.
One big concern that hasn't been well addressed is the interaction between natural gas infrastructure and electrical power generation. The 2021 Texas outage made this clear. "Five times more natural gas than wind power had been lost. When power was cut, it disabled some compressors that push gas through pipelines, knocking out further gas plants due to lack of supply."[2] If more of the Texas grid had gone down (it was close), it would have taken far longer to restart. Especially with frozen water in the pipelines. Nuclear, coal, hydro, solar, and wind plants have their own local fuel supply, but natural gas plants usually do not. The pipeline system and compressors need to be brought up first. This is especially a concern after the 2021 pipeline ransomware attack.[3]
PJM's internal 2019 study has concerns about this.[4]
[1] https://protectourpower.org
[2] https://en.wikipedia.org/wiki/2021_Texas_power_crisis
[3] https://en.wikipedia.org/wiki/Colonial_Pipeline_ransomware_a...
[4] https://www.pjm.com/-/media/committees-groups/committees/oc/...
Every Factorio player knows you never power your generator pumps with the primary power source
From the hypothetical scenarios detailed after the Texas winter shutdown a few years ago, this rule sounds unhinged from reality without mucho mucho dollars. Up to an including spare power plant(s) "just in case" a black start would be required.
I could believe it takes multiple hours just to fully start a single coal plant. Let alone align the frequencies across multiple stations in the grid.