Both Nikon P950 and Olympus SZ-16 iHS have 16.0 MP resolution sensors but Nikon P950's sensor is (1/2. ) and Olympus SZ-16 iHS's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Olympus SZ-16 iHS'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 Nikon P950.
Below you can see the P950 and SZ-16 iHS sensor size comparison.
As seen above, Olympus SZ-16 iHS has a infx Larger sensor area than Nikon P950. 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.