just because "I don't want to see more of this" doesn't mean it's up to me to influence whether anyone else can see it.
I feel like this proves more than you want. For example, is it up to you to influence whether someone sees more of something, just because you want to see more of it?
Similarly, it's also helpful to get a reason for up votes, but enforcing that a reason be given can reduce the amount of information-aggregation that will occur, on some margins. What justifies an asymmetry between how we aggregate positive information and how we aggregate negative information? Or would you also argue that up votes should come with reasons?
If you want to explore the community more, I recommend reading the Library, checking recent Curated posts, seeing if there are any meetups in your area, and checking out the Getting Started section of the LessWrong FAQ.
The Open Thread sequence is here.