Why do you consider "disagree" a negative reaction? Disagreements are potential learning experiences for both sides. I acknowledge a worded disagreement is more constructive but reactions still have some value.
A post explaining ones view that may disagree is very useful and sparks debate
There is no useful value in the emoji reaction alone
I, as a poster, don't need to know you disagree on my post itself
Others don't need to see it (it generally sparks a pile on culture)
What we all gain value from is a constructive textual retort
Sort of related to this:
I was just listening to a podcast discussing the studies and governing body reports imploring Instagram to hide likes.
Even positive affirmation (or the lack of it) via likes has been studied and shown to be a potential mental health problem.
Ultimately, it's just not necessary.
This is a discussion forum and "reactions" to what people say should probably be limited to "saying something back in a constructive fashion"
It's low effort and not a value add to do drive by emoji reacting -- I find a lot of accounts that do it never say anything at all (positive or negative) -- Sometimes I wonder if there is a bot problem on MR honestly