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.