You’re nearly right - but not quite. During the early stages of an epidemic (or any other “population growth” scenario) the rate of growth is exponential during the early phase (where resources and opportunities for expansion are effectively infinite relative to the size of the population). Later, as limits start to appear (like competition for food in classic population dynamics, or for exposure to not-previously-infected hosts in an epidemic), the rate of growth tapers off. The result is what’s known as the “logistic curve”, which has a characteristic S shape: slow start, followed by rapid exponential growth, tapering to slow finish. By quickly introducing the social distancing measures we’ve effectively brought in the limits to growth early, cutting the size of the exponential phase way down.
