I saw someone comment that "votes are public" on Lemmy but couldn't ask what they meant by that because of server hiccups going on (and now I can't find that thread again). I'm still wondering what they meant by that because it still seems hidden and there isn't even a way to see what I have done myself.
They were likely referring to the fact that due to how ActivityPub works, the server database does in fact contain all the details on exactly who up/down voted what, and that this data is publically accessible in a couple ways. So unlike on reddit, you could, if you wanted, find out exactly who is downvoting your shit.
They're public but I'm not sure they're available through the API (yet?). They're definitely in the database however, I've showcased that in this post: https://lemmy.max-p.me/comment/30714
I believe if you hosted your own instance you would have to get access because of how federation works, so it might stay as something like most apps/uis won't expose it because it's a little invasive, but it's definitely still accessible without too much work.