I'm surprised they found that there is no evidence that using these platforms is "rewiring" children’s brains. Wasn't it shown that social media companies base pretty much their entire technical decision making on psychologically conditioning not just children's brains but everyone who uses it?

Not really. There's a difference between things being sticky and actually altering the brain.

Yeah, we spend more time on social media than we intend, but I also take longer to get up in the morning than I'd like. The big question is does this alter the rest of my behaviour, or my mental state, when I'm not doom scrolling or refusing to leave my duvet?

That's a much harder question to answer, and the evidence is a lot more mixed.