This claim is not altogether wrong, but it is more than slightly misleading.
An MC cartridge does possess inductive coils, and therefore the impedance curve will indeed rise with frequency.
However, due to the very small inductive value (for example 2.5uH for Audio-Technica's air-core ART-9XA, 25uH for their permeable-core ART-9XI), the impedance rise will not start to become noticeable until the frequencies are well past the audible range.
The following link demonstrates that loading a Denon DL-103 with 47kohm, then 100ohm had a minuscule effect on the audible frequency response.
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