Is it the same for downvotes?

Yes

It's honestly a big downside. I can see it being useful for admins on their own instances to detect brigades or vote manipulation coming from different servers, but I don't like that they are public, because it could discourage people from voting honestly on topics where they could potentially be harassed for engaging

And anyone can be an admin. You can just make an instance and appoint yourself an admin. So in practice it's not limited to anybody.

It's just an option on every post

https://i.imgur.com/j5ZB8vi.png

On the regular Lemmy UI you can see the option if you're an admin (on any instance, not just the one the comment was made on)

No, it's on Lemmy too

The accuracy of the votes (lack or vote fuzzing) and the ability to view the split of upvotes and downvotes individually, as well as who voted for what

The latter point can be seen as a kind of disadvantage though. I don't like the fact that anyone who is an admin on any instance can go to another instance and see the identity of every voter on any post.

I'm new to lemmy, so I could be missing some context, but you arent making a very good pitch with this post. Java is a downgrade from rust, and unless I'm reading wrong you seem to suggest they are planning to deliberately introduce new features into this java implementation as a way to break up the network on purpose, which would make lemmy instances obsolete, and you sort of present it as a good thing and suggest its a deliberate political move on behalf of sublinks. But you didn't even explain in your post why lemmy exactly needs to be replaced. So you are calling lemmy toxic, but already this new project is just seeming very underhanded and manipulative by its very existence. As a user who just wants a better reddit alternative, reading this post makes me feel like I stumbled upon a project motivated by a grudge (just based on the way it's phrased) and you leave me more inclined to speak out against it than endorse it, since it seems like an attempt to divide the network, and I've seen what happens to divided networks where instances have different features and refuse to work together (just look at XMPP). So unless you can explain what is wrong with lemmy's development or roadmap I think everybody reading this should be very skeptical of sublinks and cautious of the threat posed by projects like this in general.

It doesn't meet every requirement you listed but privatebin.info supports file attachments, configurable expirey, and burn-on-read, and is fully end to end encrypted

is plasma any good yet? I last used it in like 2019 and it was too buggy. I've heard it's gotten better, but I haven't had the chance to test it

1 step forward, 4 steps back!

I don't know, but I wouldn't recommend OpenShot because it just gets really laggy when adjusting the timeline, and it lacks certain workflow features that you'd just expect mature video editing software to have (like the ability to move or delete keyframes)

none