Given the Empire only employs cross eyed marksmen, I think the good guys can be forgiven for grandstanding given their foes incompetence.

I sort of know what you mean about suspension of disbelief with less realistic fight scenes, but I think it depends on the tone of the film. A unrealistic fight scene can be utterly entertaining in the right circumstances.

Star Wars I do not see as particularly grounded in reality, it follows the big flashy and stupid style and is subject only to it's own nonsensical rules, the lightsaber battles are just one aspect of this. There are also the space battles where lumbering ships fight at point blank range and have ridiculous vulnerabilities, or the so called elite clone/storm troopers who are terrible marksmen and wear useless armour. Star Wars fight scenes are meant to be flashy and entertaining but that's about it.