Sony has realeased the specification of IMX461 the sensor mounted in the X-T3. Fuji has chosen to let it work at 14 bit, but there is the possibility to let it work at 16 bit with a S/N better.
It is a right choise because working at 16 bit, the speed decreases, but in the X-H2 , Fuji may choose to let it work at 16 bit, increasing the velocity of processor, having, the body of X-Hx series, the possibility to dispose of the increased heat generated