I think it has utility, it allows people to get an idea of the communities feelings for a post without reading all the following posts.
I think that if you remove the disagree button you should remove all of the buttons/ratings and not have any at all.
Because it's 2017! We should never consider thinking for ourselves, and leave that complex chore to the 'community'?
The Informative, Helpful, Like, actually serve a purpose:
Informative: Eliminates a reply of 'thanks, I didn't know that!'
Helpful: Eliminates a reply of 'That's what I was looking for! Thanks!'
Like: Eliminates a reply of 'That's what I was going to post! or You are right on the money!'
Funny: Eliminates a reply of 'I just spit coffee on my keyboard!'.
These cut down the number of posts in a thread and make a thread easy to read.
But what does a Dislike remove?
Helping to start an argument seldom cuts post counts.
Now, you can be REALLY Helpful to me, by giving me a Dislike. I collect them. First one to 1,000,000 Dislikes becomes President of the Screen Actors Guild, or Commissioner of the NFL, your choice.