Of course, neither will happen, so there's that.
Sadly, I don't think that makes sense. Switches have a lot more to do a lot faster when it comes to the internet as compared to a phone. 100 years ago, calls were completed by a person physically moving one or more wires from one plug to another.
Better to have an emergency system that will always work - and maybe the only way to keep an emergency system maintained is to use it during non-emergencies. Hard phone lines and radio.
The actual problem people have with VoIP landlines is that they require power at the customer end. A traditional analog POTS line supplies power from the central office so it doesn't need any from the customer, unless they want to use a cordless phone, which takes more power than the central office provides. A fiber VoIP line requires power at both ends no matter what.
Note the original phones actually didn't have "central battery" as they call it. Instead each phone had its own battery, designed for about 6 months of usage, and every 6 months the phone company sent a wagon around to replace everyone's phone batteries.
We went through a hurricane in 2022 and that was an eye opener too. Most "land lines" are no longer a line to anywhere it's just a phone connected to the Internet. Anyone with that type phone had no service after 24 hours without power. My 85 uncle still (even now) had an actual land line and it worked no issues.
After the hurricane no citizen had any way to communicate. Cell towers failed when generators ran out of fuel. No fuel because gas stations couldn't pump gas without power.
My dad passed away just a year earlier he had been on an oxygen generator that needed power 24/7. I don't think he would have survived. I'm not sure if I could even have reached 911.
For awareness radio is the best solution but even emergency services radio stations are being decommissioned here in Canada in favour of Internet services.