Facebook is a spamfest of clickbait articles and posts trying to sell me watches and Shirts, that take away from the experience of using a social network.
When you click the feed you will almost never find anything that could maybe teach you something. Best case scenario you read a "15 funniest photos you would never believe!!!".
Worst case: "Share this post or someone you love will die in 15 days". Ridiculous stuff.
FB doesnt even come close in regards to the amount of valuable content i can find on Steemit with ease.
FB offers value, but finding it amidst all the filler is beyond impossible.
But FB is still larger and that add revenue that gives it mainstream credibility will keep it going for a long time.