Wizards needs old sets to become rare & obsolete, for many reasons. It helps them sell more cards, and it also gives them far more creative leverage with new ca

Wizards needs old sets to become rare & obsolete, for many reasons. It helps them sell more cards, and it also gives them far more creative leverage with new cards. They don't have to play test & ensure balanced play across the entire catalog (some stupid good cross-decade combos have showed up on accident over the years) and they have more ability to avoid rampant power creep, which according to some has been a big part of why the game has lasted.