We cannot possible manage without a landline, though, because we have no mobile signal, and aren't like to get one. Most of the things you do with a phone we do with an iPad, desktop or laptop. Having been a Microsoft Office user for decades (used it at work), I still do everything in Office, so diary, notes, finance, pretty much everything. I'm used to using a proper camera, and that's got wifi, so it just sends photos direct to the NAS when within wifi range, so we can easily access them on any device.
99.99% of the phone calls I make or receive are at home, where the mobile doesn't work (so stays switched off). There is no prospect of us getting a mobile signal here in my lifetime, I think. We have a small community group that looked at setting up a microcell just before the pandemic, but the cost was very high, even though a farmer offered the use of his land free of charge. Same goes for several other villages around here, several have no signal and some have tried to get it sorted, but I don't think any have succeeded. Mobile coverage here is hampered by the area being dominated by EE, with all their masts working at the higher frequencies, so the signal just doesn't make it to the bottom of the valleys. The builders that came over here from Ireland to build our house couldn't believe that their phones didn't work, either here, or in the village a few miles away where they were staying. Until you've lived in an area where reception is patchy to non-existent I don't think it's easy to understand what it's like.
I know, but only if you fork out for a plan that supports it. Because I so rarely have a need to use the mobile, I have a cheap PAYG SIM, and that works fine, costs next to nothing, but it doesn't support wifi calling. That's no bother at all, as the landline works perfectly for calls, and I can't see the point of keeping a mobile on, and keep charging it all the time, when the landline just works without any of that.