I recently learned that voting on lemmy is not anonymous. Anyone can get information about who has upvoted and downvoted a post or comment.
In combination with your IP, this is a massive privacy (maybe even physical security) risk. Also, people can target you for your votes.
Sadly, this is something where I would prefer Reddit over Lemmy. Big tech scrapes data from both places anyways, at least Reddit is safe.
It’s the other way around here: Everything is public except where it’s made clear that it won’t be (e.g. email address, password).
For what it’s worth, your instance of choice is particularly negligent in regard to informing its users. Compare lemmy.today/legal to lemmy.world/legal, or their respective signup pages for examples. There’s little that Lemmy itself or the community at large can do about that 😞