But Star Wars isn't inexplicable, nor is Star Trek. The way all drama works is, if it isn't shown to be different it's the same. That's obviously referring to the structure of the universe of any given movie or book, etc. Implicit readings of plot are completely different, but as for how audiences understand a universe without it being explained to them, that's the rule.

And anyway, most of the things we see on Star Trek or Star Wars are simple to understand dramatically, and so they don't require explanation; Warp speed, or light speed? It just means going really fast and has no other bearing on the drama. Transporter beams? A quicker way of getting up and down from ship to planet. Light sabres? Just swords but made of laser that cuts through things. And so on.

It's not so much that Star Wars is inexplicable, more that it just doesn't need explaining.