>>3751534>Iso is constant
No, iso is arbitrary and based in how much gain is required to reach a reference luminance. Smaller pixels require more gain as they gather less light>Aperture is constant but sensor size isn't
And the lens and sensor have to work together, either on their own is completely meaningless.
If you stand in the rain, and it's raining consistently over an infinitely large plain (light & aperture), what collects more rain (light) in a set amount of time (shutter speed) a wide brimmed bucket (big sensor) or a highball glass (small sensor)?
Just because you use a small sensor doesn't mean you have to have a small brain anon.