Going into a club just to go around showing everyone a thumbs down is being an ass tbh. I can’t say whether there’s a rule against it, but it’s not behaviour that’s helpful for anyone.

For stuff that shows up in your All feed, you can downvote the post to keep it out of others’ feeds. If such posts appear too much you can block and move on. The mods have just done the latter for you.

blanket down voting every post and comment in a community

If true, this explains it all right there, regardless of the underlying issues (I mean regardless of ethics of right and wrong etc.). You could just leave the community if you don’t like the content, perhaps making your own, or make a respectful post outlining your reasoning to try to convince people, etc. But acting like a toxic asshole doesn’t seem like it’s helpful to anyone?

Again, if true.

Yeah nah you’re in the wrong here. Report to admins, block the community and move on.

YDI.

We (Lemmy users in general) have an idiotic tendency to take matters into our own hands, instead of letting the people in charge handle it, even when the later would be better for everyone. And that’s exactly what you did.

If you believe that a community promotes harmful content, report it to the instance admins. Make sure to back up your claim with studies and the likes. Don’t simply blanket downvote everything in it, otherwise you’re creating a precedent for other people to do the same with other communities.

As stupid as this is, it’s not up to you what is a “dangerous diet” and going to an entire community you disagree with just to downvote everything is petty and childish. Just block it instead.

YDI

I mean I get it’s annoying. I also think “carnivore diet” is just a dumb grift like “raw milk” or whatever. But I don’t think you have a right to complain here. Someone created a community for people following this diet, it’s obvious they will ban anyone like you who is vocally opposed to the diet.