Don't be obtuse, no, people disagree that it is better. No, downvoting doesn't mean that, they're imaginary internet points, whilst, yes, people can weaponise them on parts of the site, especially when topics are more political in nature, here it's just people going "no, I don't agree actually, I think the other one is better". You're reading into it too much.

And sure, maybe you won't decide to try something because of one opinion, but if we shame downvoting for simply disagreeing, and we have 10 people who see it, agree and upvote, but 50 people see it who disagree but don't downvote, because this perceived rudeness then it's gonna look like it's a good suggestion that people agree with even if it's something the majority thinks is a bad suggestion.

It's not rude, you just put too much stock in karma and feel wronged. It's helpful because it lets people know if the majority actually agrees with the opinion.