* Lei et al 2024 metaanalysis, generally positive associations but no causal evidence for psychosocial effects, especially when the social media use is family-directed - https://www.cambridge.org/core/journals/international-psycho...

* Balki et al 2022, metaanalysis, same thing: good for reinforcing existing real-human social connections, overcoming barriers to/increasing regularity and frequency of contact, acquiring access to resources; isolating to use outside that context; regular and frequent contact much more effective than occasional or episodic: https://aging.jmir.org/2022/4/e40125/

My overall impression seems to be what common sense tells us: to the extent it lets you overcome aging-related obstacles to interacting with real people, great; to the extent it’s brain rot, it’s isolating.