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: Obligatory RIP my inbox.
Cue tactical voting, virtue signalling and influencing. By having them anonymous you don’t have to worry about those things. There’s a reason voting on a political party or candidate is anonymous, and voting on opinions and posts should be so too.