I did try phoneless for a few years, except for a dumbphone that I kept at home for the rare call or SMS 2FA.

The biggest factor that forced upgrading was poor call quality on the dumbphones I tried. (And this was really forced by bombing a particular important phone call because I couldn't be understood well.)

Then, once I found a smartphone that I kinda liked (GrapheneOS, after Apple sold out on surveillance), there were reasons to start carrying it. Rather than simply keeping it in a drawer at home.

But fortunately not sufficient reason so far to go full Google Play.

Email, Web, maps, authenticator, camera, and calls are all things I sometimes could use when out.

Though I normally don't have to have any of those, but I've been experimenting with it for a year or so, and seeing whether it's worthwhile.