By default, every member of the community can invite the logged-in member to join their groups. If they are not comfortable with it, can always restrict group invites to their friends only.
Group Invite Settings – BuddyPress
Update on April 18, 2025
By default, every member of the community can invite the logged-in member to join their groups. If they are not comfortable with it, can always restrict group invites to their friends only.