A bit meta: what's the thing with people that are not subscribers to the community but downvote perfectly fine posts?
If it's spam, then report it.
If you are not interested in the community at all, then just mute or ignore it.
If you are interested in the topic of the community but disagree with the post, then write a comment to help with the discussion.
@Parasite_Messiah@lemm.ee and @Daveofthenorth@lemm.ee, can you please refrain from downvoting posts in communities you do not participate? There is no algorithm to train here. You might not be interested in the content, but other people might be and you end up making things hard for them to find it.