Nothing question

Someone I've known for a while recently privated their profile, and I can't see any of their profile or add them/message/follow them since it's a private profile now. I was going to read all of their reviews. However, if I log out for some reason I can see their complete profile. Is this intended? And how come I can't send a message to a private profile? I don't feel like that's a feature which should be available...