Re: Poor Countries?
"I'm not coming down on the side of fibre vs satellite, though. Too many other complex factors."
Here are some considerations that will apply, making most of those factors unimportant or nonexistent.
"Sociopolitical, for example - how many tyrannical governments like shutting down internet access,"
These systems have already agreed to comply with governmental censorship. They have to. If someone sent up a satellite to do two-way comms in an area where censorship was going on and didn't respect the government's regulations, the government would go around with radio vans and find people who are transmitting to those satellites. The dishes would be smashed and the users imprisoned. If that country had the ability to further punish the satellite operator, they would. The point being that if a government wants to cut off the internet or mess with it in a different way, they're still going to do so even with this system.
"how many twats like to set fire to cell phone towers or microwave relays?"
I've seen people attacking towers, but relays don't seem to be as targeted or as vulnerable (they're not as densely packed so the operators can afford to secure them). The problem is that, after the signal goes from the user to the satellite, it still has to come down somewhere and go to the other services run along the ground. Satellite manages to make extra paths for the last hop from ISP to user. It doesn't liberate us from the rest of the ground-based network.
"How much of our essential infrastructure such as food distribution and emergency coordination relies on the internet,"
A lot. You can try to make a satellite web, but if the internet goes down around the downlink places, it's not going to do you any good. If you want to make those things not be so reliant on the internet, you have to use something different. Point-to-point radio link, satellites that don't downlink and connect two devices on the same network (not what these constellations do by default). Those are good ideas, but this doesn't accomplish them.
"and how resilient is ground based infrastructure to storms, fires, trawlers, civil unrest"
If we're going to worry about those things, we have to worry about several other things. First, we have another ground-based thing that runs to all these places: electrical power. Can you run the satellite receiver from a battery easily available to users? I'm guessing it takes something larger like a UPS, which most houses don't have. Second, how resilient are satellite dishes to those things? A storm can smash them or knock them out of alignment. Fires can release smoke which occludes or corrodes them if it doesn't just burn the building down. Civil unrest can cause damage if people want to use hammers. Third, you could ask similar questions about the satellites, as they may have resilience problems to radiation, collision, or overwhelming traffic. Finally, you still have to take into account that the satellites are relying rather heavily on ground-based downlink to provide all their services.