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.
Currently yes, but before they started federating they didn’t. That’s why Kbin has both Boost (retweet), and the Favourite (like) is the “upvote”, which end up here https://kbin.social/fav - and until very recently, those didn’t increase your reputation.
Kbin is (was) less like Reddit and more like Twitter with downvotes.