This question focuses on the UI of the new tooltips (not the text), and it has the following sole focus: Completely undoing the recent change.
Just simply undoing this will be a single change with a single focus.
I originally posted this as an answer to this other question. However that question ended up going in a completely different direction, which basically just had to do with the text, with basically nothing to do with the UI. So whereas that question became about the text, I will now post my own equivalent about the UI. If this is a concern about duplication, let me know, and I'll delete the answer on the other thread to keep this question open.
Regarding the new tooltips around the upvote and downvote buttons, I strongly suggest changing the look and feel of the UI back to before.
The older style of tooltips that this site has used work great. In particular, they are unobtrusive. For example, there is a small, roughly 1-second delay before they appear. And even when they do appear, they are small and do not grab all attention away.
Unfortunately however, these new ones tend to look and feel more like pop-ups. They show instantly every single time the cursor hovers over one of the upvote/downvote buttons, they are much larger than before, and they immediately steal all attention from the rest of the page, over and over again.
On another question, I mentioned a few common reasons that these sorts of notifications are really a bad thing. I will use a similar, yet slightly different list here:
They add clutter to the site's UI.
They are typically not necessary or relevant for the user.
They distract the user, and they are very stressful as a result.
Regarding reason #2, who on this site does not know what an upvote or a downvote is? This is extremely common and standard all throughout the Internet, and it is only a slightly different expression of the same mechanism as likes (such as on a Facebook post). Yet when blaring notifications instantly show every single time an upvote or downvote button is hovered over, it constantly distracts the user, and it creates stress.
If you really feel this information must be present, then please at least revert back to the standard, much less obtrusive tooltips, which have timed delays and do not use excessive space and glare.
Personally I feel like I'm using these sites less now, specifically as a result of this - yes, small, but nonetheless constantly recurring - stress factor. If not that, I'm probably at least casting fewer votes now, because of this being almost kind of a deterring factor.
If you feel this information is necessary, a perfect example of how these tooltips can be improved is as below:
This is the standard tooltip that is used not only on SE itself, but also all across the Internet and desktop applications (with minor variations). It contains a timed delay, and its layout is also unobtrusive. If you don't want to get rid of the upvote/downvote tooltips entirely, then I strongly suggest switching them back over to this standard, heavily user-accepted type.