I think it's just going to bring problems. I'm the kind of person that doesn't mind giving her honest opinion and I am not one to "soften" anything, but I also think that opinions should be given when asked for, especially negative ones. I had a Facebook friend whose posts I didn't like. At all. Know how I handled it? I deleted them from my feed. If I don't like the kind of negativity they are putting in my feed, I just don't need them there. I don't have a need to give people reasons why I do/say what I do/say. But if I was asked why I deleted her, then a simple "because you put too much negativity on my feed and I don't want that in my life" would do.
If someone doesn't like something, they don't need to "Dislike" it. Then can just ignore it and even block it if they want. With so much bullying going around especially online, this dislike button lends itself to this. I think people that would use a Dislike button really don't care about others feelings and give their opinion WAY to often when not asked. Apparently they were never taught "when you have nothing good to say, don't say anything at all." Of course, this lesson in life has its exceptions: if someone asks for your opinion, give it honestly. But if someone doesn't and it's negative: keep your trap shut.