AITA for refusing to buy my kids a smartphone before high school?

My kids keep telling me that “everyone else already has one.”

My answer has always been the same: they’ll get a smartphone when they start high school, not before.
Until then, if they need to call me, a basic phone is enough. They have a Nokia 3310 (the new one).

They think I’m being unfair and that I’m isolating them from their friends. Some parents also think I’m being too strict. My wife thinks I’m too strict.
Pressure is high!!!

I just don’t think an 11- or 12-year-old needs social media, constant notifications and unlimited internet access in their pocket.