That could also be an option, although an additional manual step might be slightly less convenient, especially in case you want to “debug” the command (i.e., regenerate multiple times with varying parameters).
Another potential benefit of entering the PW in the field is that the generator could take care of proper escaping – think, if the password contains spaces, quotes, asterisks, $ signs, or other bash shenanigans. (That, by the way, doesn’t seem to work right now, @OP.)
Another idea could be to allow entering an env variable name instead of a value.
If you are on a dev machine iterating quickly, just set the basic credentials up in ~/.mylogin.cnf[0] and you don't need to worry about supplying those options on the command line at all.
For those confused by this comment, "It" refers to the coal power plant from the article, not the Kahe powerplant in the parent comment. I definitely went down a bit of a rabbit hole trying to confirm/deny that Kahe or Waiau shutfown before realizing my confusion.
Think of anyone you’ve encountered whose native language is different than yours. Chances are they had an accent. The less fluent they were, or the more different their native language was to yours, the thicker the accent. The thicker their accent, the harder they were for you to understand.