Assuming both sensors have the same pixel count, the resulting images also have the same pixel count but the image taken with the monochrome sensor would resolv

Assuming both sensors have the same pixel count, the resulting images also have the same pixel count but the image taken with the monochrome sensor would resolve finer details which get lost when doing the color interpolation with the color sensor. This can be nicely seen with the Leicas, as they usually sell a Monochrom with the same pixel count as the color version.