A321 Captain reported refusing an aircraft for ETOPS operations due to fuel quantity indicating system degradation and repeat occurrences of the same problem.

Narrative

Refused ETOPS flight because of arrival fuel degradation one day prior that led to diversion to ZZZ1 while enroute ZZZ2-ZZZ. While troubleshooting and one flight ZZZ1-ZZZ were apparently conducted; they in no way replicated the actual fuel load and conditions on a flight from ZZZ-ZZZ4. Contacted Dispatcher to discuss the issue; we jointly agreed that taking another aircraft was the safe option. Flying the refused aircraft on a domestic transcontinental flight with full fuel prior to sending it on an ETOPS flight where options are obviously quickly limited in the event of a fuel loss issue is the responsible thing to do. While I understand that there are numerous carriers and other fleets that might face the same issue; my concern really falls under a recent spate of numerous recurring maintenance write-ups that follow a pattern of 'Discrepancy-Troubleshoot-All OK' only to have the problem resurface a flight or two later; followed by 'Discrepancy-Troubleshoot-All OK'; problem resurfaces again; MEL problem; wash rinse and repeat without actually fixing the problem. Couple that with a few recent misapplied MELs and; frankly; I am concerned about Company compliance with the spirit and intent of the MEL; namely the portion that states: 'When operating with multiple inoperative items; the interrelationships between those items and the effect on aircraft operation and crew workload will be considered.' While I recognize that I am the last line of defense in the safety chain and have no problem whatsoever exercising that responsibility; it has to be noted that Company senior management team has publicly recognized how much they have failed in operating a reliable airline; they have yet to connect that message with viable actions in the field. Require every senior manager involved in flight operations to read the preamble of the MEL and ask the hard question as to whether or not they are fostering an environment that enables the spirit and intent to be met or are they instead far too concerned about completing flights and how it impacts their bonus scheme.