Communities need their MODERATION abilities fixed ASAP ... a community should be able to interact and be able to keep out all the negative influences they want... a community is an owned location you should be able to decide your experience.
Heavy emphasis and focus on rewards perhaps connects all content across all communities presently so that aspect may still be impacted and it does seem that aspect of the experience was what you were impacted by the most... but perhaps we should find ways to make everything else more important and voting less important so that outside negative actors can't impact communities as much as they presently can.