Why is the smash record set on a headlight racket?

Yonex recently released their Nanoflare 1000Z which is in my understanding a moderately headlight racket (perhaps leaning a bit toward even balance) with a very stiff shaft. This would align with the pattern of other Z-series rackets from Yonex.

My question is, even when Yonex has very head heavy rackets like the 99 Pro and ones that are both very head heavy and very stiff like the 100ZZ and Z-Force 2, why is it that the smash record was set on a much headlighter racket? Was it done on the 1000Z for the sake of marketing a new racket, and it could theoretically be done on any stiff racket? Or is that a headlight racket allows for a greater acceleration of the racket meaning that more momentum is transferred to the shuttle? Or is it that professional players can use their body weight in the smash so the headweight of the racket becomes less of a factor?

This question is set in the reasoning that headheavy rackets mean higher overall power in a smash, but now I believe it is not as simple as this. Why?

Here is the video concerned:

Thanks!