Having multiple different reaction buttons would legit be nice:
I agree
I disagree
Thoughtful
Contentless
I learned something
I changed my mind
This way we could eg. express that we disagree with the post, which was thoughtful and a good effort, and didn't change our minds but still learned something.
One huge poison in a lot of modern discourse is that accepting your interlocutor has a point should mean you start to agree with them. Why? Some of the best things I've ever read in my life didn't change my overall stance on a subject, but gave it a lot of new nuance and depth, and appreciation for the person talking.