Blackbox debug mode (unfiltered gyro)
The blackbox debug mode selects extra data to log — crucially the unfiltered (raw) gyro, which is what makes deep filter analysis possible at all.
Without the unfiltered gyro you can't see what the filters actually removed. PIDoctor uses filtered-vs-unfiltered to judge filter effectiveness and tells you honestly when this data is missing. Set an appropriate debug_mode in the Betaflight blackbox tab before your tuning flight.