This is a good way to talk about downvotes. As you, I do think this is needed as a feature.
I agree with you; forms of auto-downvotes, i.e., downvoting forever, are not right. I know a user who is constantly downvoted for - partially - the wrong reasons. This account is not following the rigid process to be removed from the ban list. Unfortunately, since this user is very committed to HIVE, he refuses to create a new account, he continues adding value to HIVE while being downvoted to zero reward value for the past few years for every single post he creates. With this, I try to say that the downvote feature can also be a somewhat abusive feature.
This is why most people who downvote do not a leave a reason when they downvote
You are so right. When I mute (in a community I am admin for) and/or downvote posts (in the same community), I usually get lengthy discussions. Interestingly, these are users not reading the profile for the community, not following the 'rules' and 'guidelines' for the community. Normally, these users hardly interact. But when I mute them, or downvote them, suddenly they wake up and start to fight verbally, using all sorts of arguments why they shall not be muted and/or downvoted, stretching the rules/guidelines clearly presented in the community profile, to a point that can not be defended objectively. Some of them return with similar posts that - again - are not following community rules/guidelines, even after previous heavy debates. Humans are an interesting species, that is for sure 😆
I do think we need a website where all downvotes and mutes can be debated. Out in the open. For a user to get themselves removed from a banlist, such user needs to get into Discord. I have no problem with that, perse, but I do think any debate shall be easily viewable for anybody. Including debates that happens in other channels. Hence, it is better to have a service powered by website to create a single source of truth. Perhaps debatably downvote/mutes can also be presented to the community at large to provide a community based verdict. Something that is missing imho.