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An idea is instead of a "dislike" button, you could have a "I disagree" this allows people to say their opinions still and with that give a fair discussion at least in suggestions.
We appreciate you making this suggestion, but unfortunately, this is similar to the one here (suggested for it to be anonymous instead), which has been declined. Adding such a button may increase the risk of vote brigading, something we strictly want to stay away from in order to ensure genuineness and fairness within the thread. As for adding a "I disagree", we don't believe it's necessary since you can normally explain your thoughts/opinions on the given suggestion. Because of this, your suggestion will be considered as a duplicate, but I hope you continue to make more suggestions in the near future!
Thank you and I hope all of you have a wonderful day!