I know a lot of people are like, d00d, I got rid of my land line, like, a decade ago. But, you know, 911. Etc. Also, we still have a landline.
FCC is working with AT&T on a phased plan to replace the PSTN with an IP based system. So even if you have a "landline", in the future, it will be running through packets like everything else.
Freaky to think about the end of this very long era (which in terms of what it is like to use the phone, won't seem necessarily like the end of anything).
ETA: Somewhat elderly data on cord cutting:
One factor is the increasing difficulty to acquiring replacement equipment.
Presumably, the vendors have been seeing this coming for a while, too.