Fediverse

That isn't really going out of your way, it is the base mode of how the fediverse works. Looking at something on a different instance.
Plenty of people just use mbin and see this, without any action at all.
The point is that as it stands right now, there are already basically no restrictions. The only thing perhaps missing is the knowledge that you can simply copy paste a link into fedia or another mbin instance to view upvotes.

You can open an issue on mbin about it, to restore a semblance of restriction. But currently as it stands, all restrictions are about as fallen as they could be.

You can ofc argue that we shouldn't open another equivalent hole in lemmys webui and api, so that you can in the future remove the ability from mbin.

I would in turn argue that this system has always been egregious, and that in the same sense as banning encryption you never hit those you want to hit using incomplete restrictions. Regular users are led to believe their votes are private, while the worst dataminers or trolls will always have their instances to query all of that info.
And how could you inform people that their votes are public without at the same time telling them how to get access to that info?

If mbin removes the info, you will get another fediverse software showing it. You will get fediverse activity pub log info pages, specific vote info pages, it will never end.
Has reddit ever managed to kill the 200ᵗʰ removeddit clone?

Please instead put your effort into changing the way lemmy federates, the only way to fix this is to make vote details private, between only a select few instances. An mbin dev in the other thread mentioned PeerTube as an example implementation where you could remove vote details like that.