Edit: obligatory explanation (thanks mods for squaring me away)...
What you see via the UI isn't "all that exists". Unlike Reddit, where everything is a black box, there are a lot more eyeballs who can see "under the hood". Any instance admin, proper or rogue, gets a ton of information that users won't normally see. The attached example demonstrates that while users will only see upvote/downvote tallies, admins can see who actually performed those actions.
Edit: To clarify, not just YOUR instance admin gets this info. This is ANY instance admin across the Fediverse.
You’d have to change the specification there. That is possible but it will take some time.
Then they should do so, these issues need to be fixed ASAP.
Still you’d need a way to make votes not bound to a user and still hard to spoof.
Obfuscating user IDs via a hash or something would seem like the way to make it work. I'm not a professional programmer, I only know a little bit of python, so I have no idea if I'm talking nonsense on that front. And whilst still not an ideal solution, but sharing non-private votes with your own instance admin and have them share only the total vote count with other instances is another solution. That way you need only trust your instance admin, which is choosable and can also be yourself.
That is what it means. If you have one then go ahead.
Putting the onus on me is a shitty thing to do. I'm not the one running this site in any capacity, but this is an issue that many users are unhappy with. If the issue with the site won't or even can't be fixed, then I will simply not use the site. I don't know how many people feel the same on that front, but I'd imagine there's quite a few.