What 'tree' are you referring to? Higher order components are just functional components that accept a component as a argument and return a new component. There aren't any additional nodes added to your VDOM unless you specifically make a HOC that does that.
Then yeah you are incorrect. You are not adding any additional components to the tree. Higher order components are just a design pattern. How you implement that pattern will decide on the component tree, but there is no additional "wrapping" penalty for using them.
