Disagreeable food, filthy aircraft, bad handling of operational upsets or downright rudeness from an employee I'd complain about. But a disconnected crew I'd take in my stride. I'm aware that such complaints can have a disproportionate impact on careers.

However, you are upset enough to present your grievances to an audience of strangers, so i reckon making the complaint would be worthwhile in helping you achieve catharsis: you'd get it off your chest and, hopefully, move on. So in that sense it might be worth it.

But if you are angling for a fistful of avios, it's very unlikely to be a productive course of action.