What stops Fury from going down in weight to the Wlad fight level?

It was 246 lbs for the Wlad fight, 262 lbs for Usyk

It's 16 lbs, around 7 kilograms.

Enough time to lose it and get accustomed to the new weight IMO.

He should do it IMO. His size advantage...

What stops Fury from going down in weight to the Wlad fight level?