Canon EOS C80 has a
19.0MP Full frame (36 x 24 mm ) sized BSI Stacked CMOS sensor . On the other hand, Nikon Z9 has a
46.0MP Full frame (35.9 x 23.9 mm ) sized Stacked CMOS sensor and features Expeed 7 processor.
Nikon Z9's sensor provides 27MP more than Canon EOS C80's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the C80 and Z9 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon EOS C80 and Nikon Z9 Cameras
Canon EOS C80 and Nikon Z9 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Canon EOS C80
or the
Nikon Z9 ,
including hyperfocal distance.