Created attachment 3232 [details] proposed patch It is useful, not only for the connecting user, but also for the system administrator to see among the lines in the server log information about the reason why the connection was dropped.
Created attachment 3241 [details] include connection endpoint in log message IMO this would be more useful if it included the offending client's details.
This has been committed and will be in openssh-8.0
closing resolved bugs as of 8.6p1 release