Is WhatsApp social media? I use it to talk to my friends. Isn't WhatsApp basically just Signal with less data protection? Does that make iMessage social media?
I think it is in the twilight zone between intrusive app and social media. It is not designed like Instagram, but many people do share quick snapshots/video there.
It does not have a like/dislike feature, but it does go beyond a messaging service I would say.
But would you categorized iMessage and Signal in the same categories then? And if no, why not? Those features, for me at least, are what I would expect out of anything that's not a barebones text message app these days.