The article title claims causality. The article body says the researchers didn't claim causality:
The review, conducted by researchers from four UK universities known as the Action on Digital Device Immersive Conditions Team, did not establish causal links between screen use and specific developmental conditions.The ADDICT, nice
This happens a lot in mainstream science and journalism. Another famous example is the often misquoted study (from McKinsey?) about DEI improving company results. The authors didn’t claim causality, since the most likely explanation is just that already large companies were more likely to adopt policies that discriminate based on race or gender. But virtually all news articles and company policies mistakenly referenced the study as if it had established causality.
That's a problem because "using a screen as a babysitter" likely correlates with overworked poorer parents and thus a whole host of other developmental problems