"The subset of my contacts that clicked "yes" became exposed to the public."
Not on your profile.
"Didn't Google make the public profile for me"
It didn't. If you never set up a google profile or a buzz profile, Buzz displays a placeholder profile to your contacts with the sentence "This person does not have a public profile." where the name usually is. If you had a Google Profile, your contacts are shown a placeholder profile with your name and a link to your Google profile.
Certainly in the latter case and maybe the former, your following/follower lists are displayed to you on your placeholder buzz profile, but these are not displayed to anyone else looking at the profile.