Yes, upvotes are in fact just a Like object in ActivityPub and downvotes is a Dislike object. This translates to various other concepts in other ActvityPub apps, depending on what they choose to call it or how they handle them.

I still feel like this should be anonymized

There is no mechanism for doing this in ActivityPub at the moment. Also, you may not want that because it would then also be hidden from admins and mods, who would then be powerless to discover vote manipulation or downvote brigading and other nasty behavior. Having the votes be transparent is probably better as it allows people to discover this kind of behavior much more easily.