To add to Jeremy’s reply, yes, because we don’t currently distinguish between comment-only suggestions and suggestions that propose changes to code. And since comments are private (between the suggester and recipient), the fork exists as a home for that discussion.
We’re listening to feedback and reflecting on improvements to the workflow. Also, we’d like to improve how shared/suggested notebooks appear on your profile (see Feature Request: Unlist a shared notebook) to reduce clutter, and more generally to offer ways to better organize and find your notebooks.