I think you are being a little harsh :). There is equally stupid content on steemit. I have found quality stuff being discussed on reddit and twitter. YouTube vlogs are primarily junk. I have never used fb to discuss anything crypto related. Telegram also has a few good channels.

I think most social media channels are equally balanced. Its always going to be easy to find noise on platforms that are bigger but steemit has its fair share of stupid posts. Just look at any ico reviews/news compilations/cut copy paste opinion pieces. Or just read through comments on trending posts. Some pockets of steemit are echo chambers for "blockchain is the ultimate answer for all problems faced by mankind" opinion. But then there gems over here as well.

And sometimes people write in haste. They aren't able to communicate the idea well. May be i am in an optimistic frame of mind right now so i dont want to call stupid, stupid.