Useless when the Internet itself isn't powered.
I put that in the post. My Spectrum service (land internet) has gone down when the grid is down (I assume there are various relays needing power to get the service across miles of wire to my house). That's why my son-in-law brings his Starlink to my house. For that service to not be powered, Musk's ground source transmission to the satellites would have to lose power. I imagine he's got that backed up ten ways to Sunday.
It doesn't matter if it's the Spectrum modem or the Starlink modem that feeds into the parent node of my wifi mesh's parent node. Once that's supplied, the internet service seamlessly moves from there to my bridge, then from there down ethernet cables to the child nodes (the rest of my wifi mesh) throughout the house. All of our devices still connect to the same wi-fi name and use the internet as before. (Similar to an office network having a backup ISP and switching to it with none of the office workers knowing.)
The grid power was down long enough only one time for us to set up his Starlink here. So we've done it successfully. The other times we were happy with hotspotting from our phones (because the grid power came back up and restored my Spectrum service).
That's not what the history says. Joseph Daniel Unwin published that data in 1934. His findings were that empires collapse within three generations after they blow off female prenuptial chastity.
Every one. Aldous Huxley called it the most important research of the 20th Century. If families cannot raise children to build upon their forebears, it's done.