Seems kind of extreme to suggest such a drastic scenario. The possibilities are more numerous than either he’s 100% fine or dead (which, btw, you are the one “putting that into the universe). I wouldn't guess that’s what people were thinking… rather that perhaps he was in ill health, had lost interest or had other projects that were taking priority, perhaps due to practical financial considerations. Thankfully Ernest has posted an update answering this question, and he says while he has been hindered by some health circumstances recently, things are basically on track.
Happens on reddit anyway. Even though people can’t see who downvoted them, they guess. Or someone (or a brigade) mass downvotes not because you downvoted their comment but just because they disagree with or resent your comments. Reddit avoided this by ignoring repeated downvotes from one person and on profile pages.
Personally, if there’s someone who is really abrasive or I just really disagree with and find their posts agitating or distracting, I just block them and that avoids the problem for both of us.
I think it would be possible. The software would just have to record a downvote, saying “we checked out this account and registered one downvote, and everything was valid”. The downvote is only reversible on the original instance the logged in user is on, anyway, and that’s between the user and server. The identity doesn’t have to be displayed to others on the original instance or federated.
The circlejerkiness of downvoting has increased since I was first on here, when people were more likely to respond with conversation than just a downvote of disdain (or my fave, people who downvote each reply in a conversation as they reply back). But there's less random downvotes of disapproval than reddit. Esp. on kbin which doesn't federate downvotes from other instances, ha.