The difference is the money factor. The way Hive is built hp has value and power. if i hold a lot of HP means i can do whatever i want and a lot of times at the expense of other people and Hive's ecosystem. It's quite different to get, let's say a dislike on Facebook and on a post here, leading to losing all of my rewards or part of it.
It's one thing to not like what someone posts and even commenting about it but even then for example you have to be polite. It's a whole other thing to "cut" a source of income for someone if you don't like his post just before you have the power to do so. Those in power need to protect those who don't have.
I won't read a post someone made about his chicken or farm, i don't like that kind of posts because it's not related to my interests. That doesn't mean i won't respect his effort and go downvote him. The goal is for everyone to feel comfortable posting whatever they want (having some boundaries) and not fear who might downvote them just because. Ofc i am not referring to abusers.
That's my personal opinion though