Idir, I like how that does theoretically solve the issue of Luke telling the audience what’s guaranteed to happen next. The only problem is that uncertainty you’ve added in also extends to Luke himself, making him seem less sure of what he’s learned since TLJ. His return there was pretty definitive, so I’d like to imagine his conclusion on the purpose of legends was also definitive.
EDIT: What about - “Legends inspire hope in the face of fear.” ?
I think it might come down to the delivery, I think it could sound retrospective rather than uncertain, but then again he’s a ghost so maybe he can get away with a little abiguity.