Some of the best B2C customers are on FB — willing to spend, low expectations, low maintenance.
If you add IG to the mix, it’s even better.
Your typical HNer does not really fall into “ideal customer” profile for most B2C businesses. Our saving grace is our above average income profile. Other than that, on average we are tolerated rather than sought after (imho).
In my area there are groups related to a lot of different outdoor activities , and they share information, trip reports, etc. There might be some other forums for that, but they aren't as widely used or frequently updated.
I might look at my feed* perhaps 2-3 times a week; despite this, there's a good chance only one of my friends has posted anything new. Unfortunately, that particular friend is also a fairly cliché left-of-the-Cuban-Communist-Party (no, seriously) activist and 95% of her posts are "signal boosting" things I, a Brit living in Germany, do not have any connection to, e.g. "Demexit memes" or Bernie Sander's opinions about anything.
Doesn't help that this trillion dollar corporation still can't handle rotation metadata*, so if I see something and I want to share it, even if it's a good fit for my feed, 50% chance the pic looks stupid the moment I've uploaded it, to which I respond "ugh, never mind then" and forget about trying to solve this and don't post it.
* though the messenger app's web view
I know this is meant as rhetorical snark, but facebook is by far the most popular social network on the planet, so it just sounds silly.
Younger generations won't touch Facebook. It's seen as a platform for "old" people. So Facebook is on a modest decline. (Enter Instagram and Tiktok and all that to fill the void...)