Is CRC32C (any) better than CRC32(B)?
What does «CRC32C (alias Castagnoli) is better than CRC32B in detecting errors» exactly means?


Multiple metrics are used in the original article. One is: when we restrict to messages of equal length differing by at most some low number of bits (e.g. 4 bit), CRC32C gives certainty of error detection up to a larger message length than CRC32 does. This is confirmed independently. Variations consider the probability of error detection for messages slightly above the threshold of perfect detection on either the message length, or number of bits in error.

I'm not sure that the 66 vs 44 collisions found in the question is statistically significant, or the cause of that if it is significant.