For one an MM cartridge has 100s of windings around four iron or ferrite cores, I’m not sure which and a magnet attached to the end of the cantilever that moves inside the field of the cores and windings. These are highly inductive and act like an antenna that is very sensitive to EFI from sources like your turntable’s motor subsequently increasing the noise level.
Your MC has a few windings of copper wire wound on a cross shaped former made of iron at the end of the cantilever that is usually attached to a rubber mount in front of a fixed magnet and in spite of it’s lower output is much less sensitive to nearby electrical noise producers.
The final word though is that your Ortofon uses a nude fine-line diamond stylus which as a rule tracks quieter than any other stylus family not using that kind of geometry. I also think they sound better across the audible audio spectrum than anything else.

