You are talking about censorship imo.

Assume following cases:

Therefore, people will see it and thus there is a reason for people to see it. What is the reason? In my opinion, it's to affect the opinion of other people. Yes, we kind of do the same with upvotes. But with downvotes, I see the argument to further go down this path like HN and reddit did: making comments harder to read or hiding comments which leads to some sort of censorship.

I see no reason to implement this. What effect would that have?

Therefore, I argue to implement personal blocklists: If YOU don't want to see comments from a specific author, just add him to your blocklist. Problem solved, no?

We can argue how effective this will be since everyone will have to maintain their own blocklist. But then, we could just choose if we want to use the blocklists of other people for example etc. That would still be a personal choice.

I think this is the way, not just throwing downvotes around and "supressing" other opinions