We seldom use our landline but would still retain it. Not so much for broadband but for the guaranteed connectivity. We live in an area with poor mobile reception and have to use signal boosters as it is. If the network goes down we would be out of contact. If our electricity supply goes down we would also be out of contact as signal boosters wouldn’t work. Prolonged power outages would mean not being able to charge either a mobile (unless sitting in the car with the engine running) or even a cordless handset. To avoid any of these scenarios we have a cheap corded phone costing around 5.99 that we keep in a drawer in the event of an emergency. We also have triple cordless set but, as I said, they are also affected by power cuts so the good old plug and play handset is a cheap, reliable backup.