I think you're 100% correct. The only value that Facebook adds over a website is allowing people to write low quality comments for likes on every post. If people want to give feedback, they can write an e-mail, send a letter, or gasp go to a town hall meeting in person. That requires effort though, and so most Facebookers won't bother, which would be great. Writing snarky, uneducated comments is not engaging. Facebook is not needed AT ALL.