The best part of the fediverse is that anyone can run their own server. The downside of this is that anyone can easily create hordes of fake accounts, as I will now demonstrate.
Fighting fake accounts is hard and most implementations do not currently have an effective way of filtering out fake accounts. I’m sure that the developers will step in if this becomes a bigger problem. Until then, remember that votes are just a number.
10 votes within a minute of each other is probably normal. 10 votes all at once, or microseconds of each other, is statistically less likely to happen.
I won’t pretend to be an expert on the subject, but it seems like it’s mathematically possible to set some kind of threshold? If a set percent of users from an instance are all interacting microseconds from each other on one post locally, that ought to trigger a flag.
Not all instances advertise their user counts accurately, but they’re nevertheless reflected through a NodeInfo endpoint.
Surely the bot server can just set up a random delay between upvotes to circumvent that sort of detection