Indeed yes the command ‘bench setup help’ no longer exists!
frappe@ubuntu:~/frappe-bench$ bench --help | grep help
–help Show this message and exit.
rebuild-global-search Setup help table in the current site (called…
setup-global-help setup help table in a separate database that…
setup-help Setup help table in the current site (called…
Instead try ‘bench setup-help’
That worked for me
frappe@ubuntu:~/frappe-bench$ bench setup-help
Syncing help database…
frappe@ubuntu:~/frappe-bench$