This is outright untrue.
If "all of the other options are better" it's bad. Game balance is more important than just player capabilities, it's important because it means that for all jobs to clear the content, all content must be clearable by all jobs. Sounds obvious, right? Well if we have something that is the weakest in its role, then all content must be doable by all weakest in that role, so then what happens when you bring something better than the weakest? It trivializes the role altogether outside of taking yourself in at a disadvantage and choosing the worst one. We literally see this in real time in dungeons when Party members die on bosses, making it more apparent than ever with the new dungeon difficulty, where PLD, WAR, and GNB can solo entire bosses, but DRK just eats crap and wipes it.
Being possible but the worst option is always bad.