Landlines seem to stay functional during weather events that knock out electricity.
Plus, my wife's parents (both in their 80s) live in an area with no cell coverage. They have to have a landline so we can check in. We made sure they bought an old-fashioned phone that doesn't rely on mains electricity to function. Very reassuring this winter with the unusual cold and snow.
We have the cable bundle, so our phone comes down the same pipe as the TV and Internet. The phone has a battery backup for when the electricity goes down (which reminds me it probably needs replacing). We have basic cable and rarely watch any TV, but I wonder if cutting the cable and subscribing individually to all the suppliers would be any less expensive than sticking with the bundle.