[sudenmorsian]

It's been acknowledged in the meteorological community that reconnaissance wind speed estimates for storms in the 1950s and 1960s have a high bias in the most intense storms, as the field was still in its infancy during that time period. Further advancement in later decades has improved the confidence in the estimates.

No conspiracy needed. After all, the first time a hurricane was intentionally flown into by a storm was only in 1943: https://en.wikipedia.org/wiki/1943_Surprise_Hurricane. The 1950s and 1960s are not that far removed from that initial attempt.