You are, of course, assuming the movie and/or producers won't be mega-retarded which may be giving them a LOT of benefit of the doubt.

You know all the air will be sucked from the cinema at the midnight premier when the cross guard get's slashed off leaving naught but popped out eyeballs and deflected anger.

But slashing off the crossguard would require the film have a level of self-awareness that's far beyond what Star Wars can be expected to have.

But if they had lightsabre-resistant materials like gloves for the crossguard, why not just make a whole suit out of it and wear that instead of flimsy robes?

That would be Mandalorian armor. Unfortunately, Mandalorian iron is both rare and expensive, and finding artisans capable of crafting it into proper suits of armor is rarer still, particularly in the years following the rise of the weak, decadent, and self-serving New Mandalorians.

Remember: even under the best of conditions, Mandalorians love to hate the Jedi Order. Getting a nice suit of beskar steel, while not impossible, is highly improbable; roughly analogous to a European knight coming into possession of a fine Japanese katana.

Another thing worth pointing out is that few Jedis, at least since the days of the Old Republic, have ever had to fight a serious, life-or-death battle against another lightsaber-armed opponent. Even during the Great Purge, Jedis were hunted mostly by Clone Troopers and robots. The extra protection afforded by Mandalorian armor simply wasn't necessary.

Finally, Jedi are notoriously stupid and resistant to change. The Jedi Order is highly orthodox and conformist in nature, establishing strict, caste-based, almost medieval social orders that remain unchanged for tens of thousands of years. Simple innovations like, oh, say, *a frakking crossguard for your sword* escaped them for all this time. Why would they ever do something so radical and inventive as to develop armor for themselves?

Ah ya, that makes sense; it goes back to my old RPG argument: the world is doomed and everybody knows that you're the only person who can save it, so WHY ARE YOU CHARGING ME FOR THE BUTTERFLY EDGE? Seems like most battles in Star Wars are a little more spontaneous, and even if the Dark Side won, it wouldn't really effect local merchants any more than a republican victory. Just so long as they don't get their planet blowed up.

You have lightsaber resistant armour? I'll just crush your throat or throw you down a well using the force. See ya.

Well yes, that's something else too. The Sith are capable of doing so much more than just waving their lightsabers around; what would armor matter to a fistfull of force lightning? Jedi, being stupid, are of course incapable of thinking outside the box like that, but the Sith's innovative approach to problem solving would have rendered their enemy's armor far less effective. Perhaps this is why Dark Side practitioners are more prone to being depicted with armor, and Jedi less so - because the Jedi knew they'd have no chance against the superior tactical prowess of their Sith opponents anyway.

+3 for skallagrim, but this subject is beyond nauseatingly stupid.

Obviously it's made out of mandolorian iron, since cortosis would short circuit the lightsaber and it would never be able to initialize.

I mentioned that in a previous video. Hand slippage is definitely a problem with guardless swords, particularly during thrusts, but I do not believe it would be much of a concern to a lightsaber wielder. The blades are practically massless, and I doubt there would be much, if any, deceleration when you thrust one into a target. It is also possible that the notches and seemingly pointless embellishments on a traditional lightsaber handle could provide the friction and leverage needed to stop one's hand from slipping up the blade; Scholagladiatoria recently did a video on Gurkha kukris, a weapon which is famously sans guard, wherein he argued that the raised bands found on antique kukri handles served this very purpose.