Yes, but "social media" is a broad spectrum. On one end you have "profile-less" social media, like forums, and the other end is "profile-rich" social media, like Facebook. The privacy implications of the latter are far worse than the former.

The test for me in defining social medial is whether its core is based a graph of connections. This is where you lose control in, for example, FB: Meta can infer many details about me without me ever posting anything, such as figuring out my home town based on relatives and school friends -- many other examples.

And this is why I no longer use any Meta products.

What I can do is help my family and friends understand the choices they are making (e.g. use Signal to talk to me). That rush they feel posting something has effects on people in their graph and now they at least understand that and pause.

Another example is ancestor "research" type sites, or DNA tests to find "your true ancestry". I had no choice a cousin of mine chose that as a hobby.

Only if you think forums, 4chan or whatnot from ye olden days are also "social media". HN has no friends feature, no curated algorithm, no way to discover creators...

I do. Primeval social media, sure. Social media that predates the term "social media," even. Nearly all things exist before we agree on a name for them, so that's nothing new.

All of those services you list are examples of an online medium that exists for the purpose of socializing. So yes, they're all forms of social media, even if they're considerably less structurally harmful than something like Facebook.

HN only violates your privacy if you write your personal details into comments. Facebook violates your privacy in ways that only talented engineers can understand.