This method only works within your magazine, and will remove downvotes or upvotes on comments as well as posts.
To implement it, go to Magazine Panel -> Appearance, and enter the following in your CSS box to remove downvotes:
{span style="color:#323232;"}.vote__down { display: none !important; } {/span}
and/or for upvotes:
{span style="color:#323232;"}.vote__up { display: none !important; } {/span}
Example with downvotes removed : @13thFloor
Many thanks to @Anafroj for writing the original CSS code, and suggesting it as a way to combat trolls. Note this test shows that standard CSS works in Kbin, but you do have to replace <> with {} to get it to parse properly.
This isn’t a perfect solution, but it should mitigate the amount of users that try to sink communities through downvote spam.
I never really saw the point of downvotes/reduces on Lemmy and Kbin. There isn’t an equivalent of those actions on other Fediverse projects (except if you count reactions on Pleroma) and it causes problems like what you have described.
I use the kbin enhancement script’s option to hide the reduce button because I have no reason to touch it.
Reddit has downvotes as a means of rating down content that doesn’t contribute to the discussion or is spammy, but it tends to be used as a lazy “I disagree” button that attracts bandwaggoning. Why put in the effort to explain why you disagree with something when you can just hit the down arrow and be done?
I’m coming to that conclusion myself - thus far in my experiment on the 13th floor, I’ve had one subscriber leave, but gained another five since. I’ve left a pinned thread up as an opportunity for folks to comment, but haven’t heard any complaints other than the ones here, so it seems like most of my readers agree with your assessment.