Maddy, I'm not saying don't carry one, but I know for certain that here in CA, people are out in the wild without a clue or adequate gear because I read about them or see them on the tv news being rescued fairly regularly. Do they use their cel phone to call for help? Often.
But, if they had a small pack, some food, a headlamp, and a map and compass or GPS, they wouldn't be calling for rescue because they wouldn't have gotten lost in the first place.
Wait a minute.
As long as there has been hiking there have been unprepared hikers taking to the woods and hills. This phenomenon did not start with advent of the cell phone, by any means. Cell phones do not cause unpreparedness, or lost or overdue hikers. To make (or imply) such a connection is absurd.
The reality is that in the BCP (before cell phone) era, perhaps a higher percentage of the unprepared either perished or became seriously hurt or ill, or a greater percentage managed to self rescue on the basis of their own grit and imagination. (Or some combination of the two.) We probably never heard about many of the self-extractions involving unplanned overnight stays in the woods, or ones that involved relatively minor, even if painful injuries in an era when it wasn't so readily possible to share tales of such exploits for all in a vast audience to digest (pre-internet, or more accurately, before internet service was ubiquitous) .
Furthermore, if there are greater numbers of the unprepared out there today than in days of yore it probably has more to do with a combination of factors than with cell phones. Consider the internet, "reality" TV, leisure time availability, increased disposable income to support playtime, fitness mania, and a host of other cultural things that attract new people to the activity. They bring their cell phones, imported from a general lifestyle.
Also, having adequate equipment is no guarantee that a party will not run into trouble, by any means. Folks have to know how to properly use map, compass, GPS and all the other paraphernalia in order for it to do them any good. Not that learning those skills is difficult, but they do have to be acquired. Gear alone never protected anyone. Knowing how to make use of it has prevented uncountable inconveniences and sad stories.
Finally, there is the very substantial probability that the authorities will become involved and see the incident through to closure when a distressed hiking party makes a 911 call on a cell phone. Once that happens it becomes a matter of public record for all to see.
G.