Unwinnable fights are perfectly fine to me and have been a staple of many JRPG's and in quite a few of the other Final Fantasy games. The only people who seem to have an issue with them are those who want to be able to slaughter or subdue any and all who dare to stand in their way, usually under the pretense of 'realism'. Though that realism, as pointed out earlier, mysteriously doesn't extend to the player character and their major allies.
Beatrix was never defeated in FF9, despite being fought multiple times. It made her a very memorable character, especially since she sided with your party after a certain point in the game. I just don't understand how some you can seriously imagine a diminutive 'waifu' player character performing the various feats that they do in-game but somehow it's too much for a hardened, seasoned combatant like Ran'jit to be successful at driving your character off.
Here's hoping we see more situations like it in the future!