An article in the Washington Post (behind a paywall, no doubt) says that only 27% of US households still have a landline phone, a percentage that's dropped markedly in the last few years. The highest rates are with older people in the Northeast.
We're old, but we're not in the Northeast. (The Northeast factor is due to the dominant company there being Verizon, which pushed customers to sign up for advanced Internet plans early, when landlines were still common, so those were part of the package and most of the customers still have them.)
So why do we have one? It's not just because we've always had one, though that's a factor. The main reason is that, at least in our situation, a landline is more reliable. And that's an old copper-wire landline. Most people still with landlines have voice-over-internet, the article says. I was almost lured to sign up for that, but I'm so glad I didn't.
1. If the power goes out, your internet is out, and so is your phone if it's over internet. Copper-wire phone systems rarely go out.
2. Our internet service is unreliable. On warm days it regularly goes out at intervals. We've been trying to get this fixed for 15 years, but no luck.
More generally about cell phones:
3. Cell reception at our home is rather bad. We live half a mile from Apple world headquarters, but we can't get a reliable cell phone signal.
4. I don't like talking on cell phones. It's uncomfortable, the reception is often bad, and all that radiation going off right next to my brain doesn't put me at ease, either.
5. Cell phones in regular use have to be recharged all the time. Another nuisance. A landline doesn't have to be recharged.
6. True, landlines get more spam calls. But at least on a landline you don't have to pay for them.
No question, a cell phone is useful. Using pay phones was tolerable so long as there were still pay phones everywhere, but with their disappearance the cell phone became superior and I got one. But at least as long as we're at this house, I'm keeping the landline. And if we move, my default intention is to get another one.