I am a big fan of the "humans are social creatures" mantra. In that regard, if something is more stimulating than social interaction it is likely to be harmful but if something is less stimulating than social interaction it is probably fine. [1]
In this simple model, I would probably say books are definitely less stimulation, TV is probably about equal (I have no idea), and modern videogames and social media are definitely much more stimulating. So, books would only become a problem in the presence of other factors but social media can become a problem for anyone.
In highschool I would play high stimulation PC games while browsing the internet on another monitor while listening to music while using voice chat. I also had almost no desire to socialize while in highschool.
[1] It goes without saying that we probably can't reduce activities to a single metric like "amount of stimulation" but I think this is a useful thought experiment.