I switched to the default Twenty Nineteen theme and still the “Register” link was not appearing in the main navigation menu while logged out. I have since reverted back to the other theme I am using.
Update: When I disabled “Include navigation title” in the BuddyPress Primary navigation sidebar widget the Name field is now appearing correctly on the Profile pages.
Still don’t know why the Register link is not appearing in my main navigation when I am logged out.