My kid has had his own tablet since 6, his own PC since 8, and his own cellular since 9.
So far he hasn't turned into a domestic terrorist, and neither is he selling heroin for crypto on the dark web. Also, he has specific times when he can use his devices аnd limits on how much time.
All modern OSes have some sort of parental controls built-in, and when the native controls are not enough to your liking there are plenty of third-party software in the market.
Technology is what allows my kid to connect and play with his friend from the former place where we lived, is also the source where he learned about black holes and watched the Space-X and China's Shenzou launches. Yeah, there's quite a big amount of trash on the web, just like we had on TV.
But the solution is not pretending it is not there and hoping they won't become absolutely fascinated at the magic age of 14.
We are supposed to parent. Part of the parenting stuff means supervising and guiding in all environments your kid has contact with, including screens.
If your kid is addicted to screens, it is on you. Just delaying their first contact to the age of 13/14 won't magically guarantee they will be able to navigate it responsibly. This is just magical thinking born out of laziness.