That's unrelated to backdoors (deliberate covert access mechanisms). All parties with access to data, regardless of whether it is via a backdoor, can put that data at risk due to their own security.
This is only unrelated if you don't consider government-mandated master key escrow a "backdoor," which seems deliberately obtuse to me. Regardless, the OP's point was that this is an additional argument against governments mandating a way to access your encrypted data, because you shouldn't be compelled to trust anyone else with a "don't worry, only we will have access" sort of system.