One thing I can say from my experience is that you get out of social media what you put in. For example, the equivalent of “cold calling” on subreddits, HN, etc. tends to elicit a lukewarm response if you haven't shown that you are willing to participate in the community itself.
I think it can come across as torrent-level leechy.
I think you just have to demonstrate you are willing to be an active member of a community (Metafilter, Mastodon, Subreddit, HN, etc.), and then others will be more receptive to what you have to offer since it'll feel more organic.
But it can be a total crap-shoot sometimes. There is no correlation between the amount of time I've invested in a given project and the subsequent reception.
Life unfortunately is not like the movie "Field of Dreams".