A C172/C182 is able to take quite a fair amount of ice, so even if there is ice building up, it rarely is an immediate emergency.
Like any plane, a 172, or 182 can withstand a pile of ice - as long as it's parked safely on the ground. In flight is a very different matter! The discussion of the hazards of ice accumulation on non deiced planes is comprehensive, though we can go through it again if it needs to be refreshed. Succinctly, Cessna says: "Flight into known icing conditions is prohibited". Could it be more clear? I speak from first hand experience, if ice is accumulating on a non deiced airframe, it
is an immediate emergency!
Usually the fear (not to say German Angst) is far worse the actual possible threat.
And it is acting based upon that fear, and avoiding flight into icing conditions, which will keep you alive!