Both Leica CL and Sony A7c have 24.0 MP resolution sensors but Leica CL's sensor is APS-C (23.6 x 15.7 mm ) and Sony A7c's sensor is Full frame (35.8 x 23.8 mm ).
Since Sony A7c's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Leica CL.
Below you can see the CL and A7c sensor size comparison.
As seen above, Sony A7c has a 2.3x Larger sensor area than Leica CL. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.