You can digitize and lossily compress an NTSC signal significantly without losing much detail; that's why I call it redundant. Compression removes redundancy.
In ATSC the tradeoff between compression and error correction is such that a noisy channel is far more likely to cut out or otherwise be unusable than it would have been in NTSC.
In ATSC the tradeoff between compression and error correction is such that a noisy channel is far more likely to cut out or otherwise be unusable than it would have been in NTSC.