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.
Because they’ve not ever done a data request from Reddit, I imagine. Reddit stores a COLOSSAL amount of information on you. The bits that they are willing to provide are concerning enough; I do wonder what they have that they don’t reveal. For example. your ENTIRE history of IP connections seem to be stored (because there’s a use for a 3 year old IP record, you know,) all of your chat messages (no way to delete those either,) associated accounts (I am guessing this is "accounts we think are you too, but I don’t know…) …so I’m not sure why Lemmy / Kbin / etc get the hate here.
I think Kbin and Lemmy could be better about disclosure, but there’s nothing inherently shady about the way they’re set up. Downvotes being revealed, I am torn on. I tend to lean toward private, but I see arguments either way.