I like smartphones. I own one. I'm totally fine with them. The latest one I own has a very generous battery life which hasn't degraded significantly in 2-3 years, and charges really fast. You can configure the notifications such that nobody can bother you when you don't want them to.
It's so freaking nice that I only need a single device to do everything, like paying for stuff, listening to music, reading a map with GPS, tracking my running distance, tracking exercise progression, package deliveries, communicating with my family and close friends, reading manga on the train, reviewing and merging Github PRs on the train, reading work mail, ordering food, booking an uber, tracking flight schedules, looking up transportation routes, secure 2-factor authentication, etc.
Doing all of this would either be a super hassle or impossible without it.