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 The linked transactions have a large number of sigops (241). 

Default bitcoin core transaction selection treats sigop's as though they have a larger size than they do. This means that these transactions are treated as though they have a significantly lower fee rate (half in this case)

https://github.com/bitcoin/bitcoin/blob/82ba0f80a0b56bb160c8be1fddd82dbbc4fb3947/src/policy/policy.h#L37

static constexpr unsigned int DEFAULT_BYTES_PER_SIGOP{20};