That is, users who clicked the "Subscribe" asterisk icon on the site.
Do you mean user clicks "⭐Not following" located on the right-hand side of the menu bar?
If it is true, currently, we can only see all SharePoint sites currently logged-in user is following in the SharePoint start page:
However we cannot list all users who have followed specific site.
If this is feasible for you, please feel free to reply.
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