As far as I'm concerned, all social media knows is how to exploit us. It hones in on what gets us engaged. I think that is far worse than 'knowing us' - I'd actually find that comforting, in some ways.
As an example, I don't think social networks really want to work on ending abusive behavior or harassment because often those behaviors create engagement. People logging on to argue at random people about whether or not you should've voted for $CANDIDATE vehemently all day long are people using the platform and showing up in the numbers. It's good business. Verifying an actual nazi on Twitter? People may have been angry but they expressed it _by using the platform itself_. Whether Twitter was right to verify them is up to you, but the reaction is undeniable.
But honestly, we're all bullshit artists. I would never go liking all of the stuff I like in real life on a Facebook in my name. Do I want all of my friends and future employers to know how obsessed I am with some subculture? Not really. I'd rather like things that make me look normal and fit in.
I haven't been on Facebook in a long time, but the Internet as a whole has felt worse since engaging socially as my real life identity. I felt it was more fun and genuine when it wasn't real life identities, although that ship may have sailed thanks to bots and vandalism.