If some things get downvoted way out of proportion, and those downvotes come mostly from people in certain instances, and instances have the power to block each other, it stands to reason some instance out there managed to block the instances that contribute the most downvotes, causing them to have mainly upvotes. Right?
Depends on the topic.
If you say something against communism you will get a bunch of lemmy.ml downvotes.
As an example