Looks like you’re using the Follow-plugin. I don’t have that installed, so could only chime in with some general remarks:
Every user page add it’s own class to the body element:
E.g. on the Activities page it’s .user-activity-page. On Messages it’s .user-messages-page. So I assume on the Follow page it’s probably .user-follows-page? You can use that class to only hide the top section on that page. Though you should take into account that you’ll get a jumpy interface if you only hide it on one view.
About the expanded or collapsed state of the posts, I don’t think you can target that with CSS. The plugin’s template for that view probably defaults to the collapsed post-excerpt. So you’d need to change the default right on the template.