TL;DR mitigating the weight and free surface effect plus the lever arm of being damn near the top deck would cause unacceptable knock-on tradeoffs.
Video could've been 1/5th as long IMO.
Yeah it’s pretty obvious to anybody with even a basic understanding of statics that having a lot of dense water sloshing around high up is going to amplify any oscillations or lists that develop. It’s the exact opposite of what you’d want to enhance stability.