A solution exists: ignore the upvote/downvote buttons and use the reply button. You can then address the points you agree with and more importantly the points you disagree with, why you disagree with them and make your own points. It takes more effort, but it provides a lot more value than the mindless voting buttons.

What if we just vote on individual words, and then show them all in order of popularity?

If lemmy votes are supposed to work how reddit votes were originally creaed to work, you aren’t supposed to upvote or down vote based on anything opinionated. You upvoted posts based on content validity, relevance and quality of content. You downvoted posts that lack citation, relevance, subreddit specific rules etc. But thats dating back to the days when reddit was barely larger than lemmy.

There is that, you can respond to the aspects of a post you take issue with.

Downvotes are for things that shouldn’t exist (like false information, hate speech, posts that are off topic, or just general assholery) not things you disagree with.

In the example you shared, you should upvote the comment, and if you feel so inclined, comment with why you disagree with the one point.

There is.

It’s called commenting. You leave a comment talking about the issues you had with the post.