23fbaf81_ess___Photographically_Curious__Mirrorless
[Overall] Camera shake [SLR] Larger sensors need longer focal lengths which require shorter shutter speeds or sturdy tripods for sharp images. Sensors with high pixel counts make the need for shorter shutter-speeds or sturdy tripods even stronger. If you don’t use a tripod (who does?), then the longer shutter speeds mean that you have to shoot at higher ISO values, which negates the advantage of lower noise. [Mirrorless] 
Smaller sensors need shorter focal lengths which allow longer shutter speeds before camera shake causes unsharp images. This means that you can shoot at a lower ISO and get the same sharpness and similar noise levels to larger sensors. Lighter equipment also allows you to use smaller and lighter tripods.
SLR vs. Mirrorless | Photographically Curious
Mirrorless