The mention of email is
Even so, much like how users of one email service such as Gmail can still send emails to users of another service such as Outlook, users may still view content and interact with users on any other instance in the fediverse
which implicitly says email is not considered part of the fediverse by comparing the two.
Your rephrasing changed it qualitatively. Of course it takes no position on whether Lemmy is part of the Fediverse considering it now does not have the word Fediverse in it.