Yes that's mostly enough for simple cases, but have you ever tried to discern a gcc command with 12 compilation flags enabled? It takes you half an hour to find everything you need in the man pages. 30 years after the wide scale spread of pointer devices this is IMO just ridiculous.
I wouldn't try to justify the awfully huge number of commands that many unix util implementations have - which seems like an anti-unix design movement to me - but you can at least cut down the 30 minutes of man page spelunking with man <foo> | grep -A 3 "\<flag>". Adjust -A argument as needed.
(for example, if you don't know what -A does on grep, run `man grep | grep -A 3 "\-A"`).
You can also use / in man to do a search in man. (Assuming your pager supports it, don't forget to use the home key to go back to the beginning for a new search option.)
> have you ever tried to discern a gcc command with 12 compilation flags enabled?
This isn't a 'discoverability' problem - the problem is the complex task. Most of what you're doing on the commandline isn't "gcc with 12 compilation flags". "How do I print this document?" is an example of poor discoverability on the CLI; command flags are not.
$ apropros print
bash: apropros: command not found
$ man print | head -n 1
RUN-MAILCAP(1) Run Mailcap Programs RUN-MAILCAP(1)
$ man -k print | wc -l # lp/lpr is in this list... but you have to find them in a list of 200.
196
$ man printer
No manual entry for printer
It's not great discoverability. 'man -k printer' is the best I found so far to find lpr, but it took a few goes to find it.
