Like buttons are a total disaster if you value truth and honesty, all that will happen is most people will put aside their own beliefs/opinions and post whatever they have learned will receive the most likes, both to stroke their ego and for them to be seen as popular. In a nut shell it will become like corporate controlled social media.
I was debating a moderator on another forum and because he was losing the argument he deleted the thread in order to try to stop me from exposing his flawed argument any further and most importantly prevent other people seeing it, that's when I realised the modern day tyranny is people posting online who care more about their imagined reputation and what total strangers think of them rather than speaking the truth and admitting when they're wrong.
Concensus doesn't equal the truth and what's right.
There'd no doubt also be mission creep as well whereby OCUK implements a ban system for people on the wrong end of the dislike button too many times, which will impact basically anyone who goes against the majority. In summary it would turn the forum into a virtual China with their social credit score and everyone just playing along with the game so they don't get ruined.