Instead we get more laborious origin stories than a 72-hour birth. Because origins are now how you extract an extra movie before you've even started the movie. It's the same logic that stretched The Hobbit like he was on a rack built for giraffes. If The Lord Of The Rings was made now, we'd be 27 hours into the third season, and we still wouldn't have left the Shire. But padding things out is the opposite of good storytelling.
Worse than telling us what we already know? Telling it in unnecessary detail. That's why the Star Wars prequels sucked: Instead of a few minutes of Darth Vader and Boba Fett kicking ass, they spent six years sucking. The new Star Trek took 38 minutes to even show us the Enterprise, and ended just as Kirk became captain. In the first episode of the new Thunderbirds Are Go, our time-to-Thunderbird was 30 seconds, and that was only because they had to set up something for it to rescue. The pilot wasn't two hours of Jeff Tracy touring the world before looking up to see an eagle in a storm. Because any movie that ends with a shot of what you paid to see should come with a refund.
"We're here to rescue you from half an hour of sulking child Kirk!"