Is it already too late?...
Not at all.
Just get off social media altogether.
Watch “Turn” and learn how it used to be done.
A network was built then only by people being wise and not by current means by obsessing how many “Friends” or “Likes” they have on their wall.
Unless you tell them, they have no idea what it is you are thinking or, what you are up to. This is the definition of Going Galt.
Social networks is a concept that goes far, far beyond so-called social media. You might want to read up on how social network theory is used, for example, in a military setting to track down terrorists (cf. my links above). It was used to great advantage in Afghanistan, for instance. And they weren’t looking at Facebook likes. You would be stunned at what social network theory, applied to your metadata, can tell you about you. - probably more than you know yourself.