Could disabling the main fuel tank pump damage the HPFP if it's starved of fuel or will this be picked up by the ECU via a sensor and shut it down? 2012 TDV8 Vogue (L322)

An interesting question. I don't know but one imagines that eventually there wouldn't be sufficient flow and pressure for the low pressure pump so it would throw a P0087 or similar and go in to limp/restricted performance.

IIRC the only pressure sensor is on the LH rail and nothing upstream. The fuel metering valve on the HPFP would detect low fuel input to my mind and try to protect itself.

My 2d worth. 2012 Vogue TDV8 in Aintree green over sand

Diesel also acts as a lubricant in the HP pump and possibly it would eventually damage it. 2018 SE SDV8 4.4 Byron Blue