Heroin is addictive. Physical compulsion is addiction. What you are talking about is not addiction. It shares some elements, but no one is breaking into cars so they can scroll Instagram.
What specifically do you mean by 'stealing'?
> lied and deceived extensively to gain access to devices, and repeatedly sacrificed relationships and trust for more screen time
It’s not about truth, it’s about lying to gain access to devices. Lying to gain access is a type of theft therefore stealing.
As that entire structure is illegitimate, the actions of the child are understandable.