Pp:
Fuel full of cavitation bubbles isn't likely to work very well as a hydraulic fluid.
Cavitation bubbles are full of low pressure gas or vacuum, and they occur as the fluid is torn apart by suction. The vacuum filled bubbles collapse implosively when pressure is restored and the shock waves cause local damage. This happens in a very localised area as the fluid passes from the low pressure side of a pump to the high pressure side.
Used as a hydraulic fluid under pressure, cavitation bubbles would not be present.