How much effort is ‘run command with parameter’ documentation […]
Tbh it’s less so the effort and moreso, how understandable is the documentation? A good GUI has the benefit of visual design explaining without words what may take a lot of documentation that may or may not be easily understood depending on the writer, which in many technical situations is someone deep in the jargon that has forgotten the way back to more accessible language.
Once you’re familiar with the commands, no doubt as many others have said it’s more efficient (especially once you’re knowledgeable enough to write scripts for frequent sets of commands), but there is a learning curve at play as one muddles through documentation in a similar way to an unfamiliar GUI.