Thanks, but no. At least to me, the whole point of the popover is to get a quick overview of the reactions given. I don’t want to have to click into each user’s card to find out their name. Opening the card also feels fairly slow due to the extra loading time.
I have to admit that I forgot that the pre-reactions “fold out” UI to show who liked a post also only showed avatars by default. I created a plugin for my forum to change that, but forgot that I did, and thought that the changed design was the default! 
So the whole thing looked more like a regression to me than it really was.
In any case, thanks for moving this to its own thread. It can remain as a plea to reconsider showing only avatars in places where you really want to read names.
The poll results UI has a similar issue.