Conceptually Boost and Upvote are intended for different things. That is in my very limited understanding.
Upvote is for the post only, but if you boost then the thing you boosted will be shared with your followers and is on your public feed.
The reputation calc does not look at upvotes at the moment, only boosts. This may change soon as the kbin author changes the site to be a better merge between the mastadon and lemmy concepts.
We are on a brand new developing platform. Things are changing fast, as we kick the tires and take it for a spin. It is both refreshing and exciting.
The rules of the internet remains unchanged, regardless of platform. Do not feed the trolls.