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Complaining won't get you anywhere.
Literal
Complaints [object-を] say-[even if-ても] won't-start [informal question-だろ].
~ても始まらない is an idiomatic expression meaning 'even if you do X, nothing will come of it' — literally 'even if you say complaints, nothing will begin.' だろ is the casual form of でしょう, here used as a rhetorical tag ('right?').