I don't think that's true at all. There's a lot of sources of anxiety (while on the go) that having a phone with you mitigates.
- If I miss my turn (gps will renavigate)
- If I can't find the place (I can call them and ask)
- If there's something else I need to get while I'm out (my spouse can call me and tell me)
- My tween, who stayed at home while I ran to the store, has a problem (she can call me)
These are all things (except for the last one) that I experienced without a phone, as a grown adult. And I don't really experience anymore because I have a cell phone on me.
Not only that, but a phone solves the "where am I" problem, which was such a pain when I was younger. Having to look for the nearest street signs while driving around, barely being able to read them and guessing its suffix, then searching the map index for which coordinate that street is in. Basically all problems solved by GPS. The directions feature you pointed out is basically a whole other application (replacing printing mapquest or written directions).
Don’t get me wrong, smartphones are great conveniences, I can land in a foreign country and book a hotel, a car from the airport, find a place for lunch, etc. all (surreptitiously) while waiting at passport control. That being said I making a plan with someone (and not flaking), and doing a little research/looking at a map, asking friends for recommendations, was never that hard)
We also managed without telephones, airplanes, automobiles and a bunch of other things we take for granted in modern life. I still find them useful and want them around.
I remember this life well, I guess the trick is to use only the time saving feature of the smart phone (the are enormous), and skip the time sinks... They are equally enormous :)