I kinda hope they don't have an API for that. I really didn't like it on reddit when two people would be having a debate on a topic, and one person would search the other person's comment history to find something to attack their character on to hurt their credibility. I think debates should be handled using relevant points about the topic being discussed. Attempts to attack character are very underhanded. It's how politicians debate. It almost like admitting that you couldn't make a better point than your opponent, so you had to stoop to that level.
I think having an API for votes and front ends that showed votes would encourage people to do exactly that here. If front ends started showing that info, I think it would discourage lurkers from voting, which I'm not sure we want.
Obviously there's very little that could or even should be done about admins seeing that info. Admins have full visibility and manipulation power over the DB, and I feel like this wouldn't even make the list of improvements that I think lemmy needs right now. Admins just sort of need to be trusted or people will leave your instance.