Here is a link to the identical issue: https://community.graylog.org/t/syslog-inputs-are-missing-from-fresh-installations/4827
You were correct about the missing —user. When I added it the list that was returned had the missing inputs. As I mentioned in the original post, clearing the browser cache or starting with another browser does not return the complete list. I’ve tried this with safari, chrome and firefox on a Mac running High Sierra 10.3.5