I have an athlete I've been coaching, and they have incredible core strength. Years of swimming, and lots of core work, 5 times per week, up to an hour per session.
This athlete though is not happy with where their performance is. The first thing I am doing as the coach is cutting back the core strength. This sounds like blasphemy to some, as core strength is the "in" thing. But if core strength translated to speed, this athlete would be one of the fastest around. But they're not.
Strengthen your core, sure, but there comes a point where the effort you put into getting the extra few percentage points of improved core is wasted, as you could be putting that effort toward things that actually make you faster.