Being cautious with assuming causations is usually a good idea - but it falls flat when we know the causal chains that are at work.
In the case of climate change, we know for a fact that humanity is releasing ever-growing amounts of CO2 into the atmosphere and we also know the physical chain reactions this CO2 will trigger. Predicting climate change in broad strokes is not statistical guesswork, it's just applying physics.
Likewise, we know apps are addictive because they are actively being designed that way. Maximizing user retention and engagement is what app developers do. It's how they make money and it's one of the core metrics that investors use to estimate the value of an app.
So you have someone showing signs of addiction after using a device that was specifically designed to be addictive. Occam's razor really doesn't give a lot of room for alternative hypotheses here.