As the design of a game, this timetable makes perfect sense. As the design of a world, it makes me sad. “Go forth, hero, and make your legend by following the attached schedule of events.” Someone already made that legend? No problem, the enemy will spawn, disappear within fifteen minutes, and respawn again on schedule no matter what you do.
We may have overshot “theme park” and started approaching TV re-runs.
While the content has always been completely mutable and timer-based, something about making an explicit schedule of villainy weakens the illusion.