They used to re-tell a superhero's "Secret Origins" every five years. That was the expected turn-around time for a comic book audience; you read them in your 'tweens, then get your kid brother (girls were rarely part of the equation) into them a few years later.
The fact that it's been twenty-three years since the story was last told in-continuity (Birthright started as an Elseworlds, and was only ever half-heartedly adopted into canon) is, in my opinion, way too long. I had just celebrated my first birthday when the first issue of Man of Steel came out. Where's my "jumping on point?" It certainly wasn't in the comics; my generation had Lois & Clark, and Superman: The Animated Series, and Smallville and the comics became tangential to the equation. Even in this retelling, they're sculpting it to cater to audiences fifteen years older than me, and while some good stuff has come out of it, I wish for once they'd give some thought to the longevity of the medium.