The mod banning these users is the same mod who made the posts they downvoted. This is mod abuse, turning the downvote button into an auto-self-ban button.
The message is “If you disagree with me, you will be banned”
Monitoring and banning users for using lemmy as intended to signal boost your opinion should be grounds to have all mod privileges removed. This behaviour undermines the integrity of the server and the wider fediverse.
and we allow rules in comms that ban certain types of contributions, like propaganda outlets, low value sources, *phobia
in general, not allowing contributions that moderators believe is bad for the health of the comm is an acceptable policy