If the kid doesn't have a smartphone, and looks around and sees kids who do have one, they're gonna be envious and pissed when their parents tell them they can't have one. I know because it's analogous to what I felt when I was still slumming it with my TI-99/4A when every other kid had a NES back in the late 80s.
Pfft those suckers didn't have Parsec or Car Wars or Ms. Pac Man plus the hours spent typing TI-BASIC from a magazine was less frustrating than trying to get the jumps right on Super Mario Bros level 8-2. And I'm sure Demolition Division and Meteor Multiplication are why I ended up with a math degree.
For real though I spent so much time pining for Mario 3 before my parents finally did give in. But I feel like there was something good about the diversity, like when I could play Lode Runner on my buddy's C64 (actually a 128... GO 64)
That sentiment has been changing. Kids themselves are seeing social media for what it really is.
Your kid is envious about their friends who smoke all the time. Would you buy your kid some cigarettes just so they can be non-envious?